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Citrus => Citrus General Discussion => Topic started by: brian on December 08, 2015, 12:03:23 PM

Title: new greenhouse planning
Post by: brian on December 08, 2015, 12:03:23 PM
Next spring I'm getting married.  Along with that, we are looking at moving to a house with more land (in the same area - Southeast Pennsylvania).  Wife-to-be fully supports my citrus hobby and I am planning on constructing a free-standing greenhouse at the new property.  I am hoping to be able to ventilate well enough to keep my trees inside year-round, planting most directly into the ground.  I'm not sure how realistic this is with 90+F summer high temps here.  I have just begun my preliminary research into this, so I still have a ton of unanswered questions.  I am thinking of something like this http://www.greenhousemegastore.com/product/ventmaster-30-commercial-greenhouse/commercial-greenhouses (http://www.greenhousemegastore.com/product/ventmaster-30-commercial-greenhouse/commercial-greenhouses) as the frame/ventilation solution.   I have an initial budget of ~$15-20k.  I don't have a particular size in mind, but I'm thinking at least 25'x50', which is about quadruple my current floorspace, and 15'+ tall, which is twice my current height.  I don't need to move my plants in the first winter as I will still have access to my existing winter greenhouse for the next year at least. 

(http://cdn.greenhousemegastore.com/images/uploads/1850_6405_large.jpg)

I know that Millet has a substantial greenhouse in a temperate climate that I can use for inspiration.  I imagine others on this forum have some experience with these things also.  Some of the big questions I have are...

Glazing material:  If I remember correctly, inflated PET sheeting is the best in terms of cost and insulation, but isn't very durable.   Will PET stand up to snow load in temperate states?  I've been extremely happy with the dual-layer 8mm rigid polycarbonate that I use for my winter greenhouse, though I can feel the heat loss through it in winter.  I'm thinking 10mm+ if I go this route.   It isn't cheap, but is far cheaper than something like glass.  I haven't priced glazing a structure this large yet.

Ventilation: My winter greenhouse seems to be fine when buttoned up all the time.  That is, I have zero ventilation beyond whatever leaks out from cracks in the floors, walls, etc.   It doesn't seem to be starved for CO2 as I get lots of new growth each winter.  Is this reasonable to expect for a larger greenhouse or will I need to either ventilate in winter or provide a supplemental CO2 source?  I haven't had an problems with condensation yet.

Heating:  I believe natural gas is the cheapest heat source at the moment.  Would make sense to allow some of the exhaust gasses to flow inside the greenhouse to add C02?  Obviously you would need some kind of sensors to detect dangerous pollutants or CO2/CO levels.  But my understanding is that natgas & propane can be very clean burning if properly maintained.   

Cooling:  my winter greenhouse gets above 115F in the summer when it is empty and the plants are all outside.  Is it possible to keep temperatures reasonable with only natural+fan ventilation?  It would certainly be possible to have a shade cloth either year-round or in the warmer months only.  I'm not sure how much air conditioning would cost but I imagine it would blow my budget entirely and I'd have to rethink the whole project.  It gets humid in summer here so evaporative cooling may not be effective.

Extra insulation: I can feel that the main source of heat loss in my winter greenhouse is the polycarbonate glazed face.  I wonder if it is realistic to have some kind of insulation blanket can roll down at night over the roof of the whole structure - assuming there's no snow?  I could also have grow lights running at this time as supplemental light. 

Water: it looks like most greenhouses can support gutters, which means rain barrels are an easy source of water for plants.  In addition, I would run a water line & spicket out to the greenhouse.  I know that others are using water barrels for heat storage also, I should be able to do the same.
Title: Re: new greenhouse planning
Post by: Millet on December 08, 2015, 03:40:54 PM
I'll add some comments a little at a time rather than all at once.  The north wall of a greenhouse does not add any light to the greenhouse,  in fact north walls lose greenhouse light.  On my greenhouse, I covered the inside of the north wall with 1.5 inch silver coated polyurethane insulation board. I also taped the seams of the boards using the 2" silver tape.  This reduces heat loss during the winter and provides additional light by reflecting the sun's light back into the greenhouse.
Millet
Title: Re: new greenhouse planning
Post by: cory on December 08, 2015, 04:24:30 PM
Congratulations Brian on your upcoming marriage, new house and new greenhouse!  Very exciting.  I would love to have a large greenhouse like you are planning too.  My greenhouse is only 12' × 16' so I can't provide much help beyond the basics which you have probably learned from your current greenhouse, but that experience you have gotten will help you with planning your new one.  From what I have read it is actually easier to keep the climate of a large structure more stable than a smaller one.  Good luck.  It will be interesting to read what others will recommend for your plans, and I am hoping to learn from them also.  One thing I would recommend you think about is how you could provide different environments within the structure in case you want to grow plants that need different temperatures and humidity levels.   I really can't do much with that in my small structure besides finding small micro climates.  I grow orchids and citrus in mine.  I would love to have at least a cool and a warm section to better accommode the orchids I grow that grow best cooler and warmer than I keep the greenhouse for the majority of my plants.  I look forward to reading about the plans as well as the structure's construction progress and startup.

Cory
Title: Re: new greenhouse planning
Post by: Tom on December 08, 2015, 06:32:43 PM
Congratulations on all the excitement that is upcoming in your life ! I will enjoy reading about it here because you are already way out of my league. Your situation is much different than mine but very similar to Millet. He will be an excellent resource. It sounds like you have a great start ! Bigger is better. I'd think a smaller greenhouse for plants with extremely different requirements would be better if possible. You have the citrus bug for sure ! I think the variegated minneola is the best looking citrus fruit. For my area Sasumas and Meyer lemons work best. With a year long greenhouse I guess anything is possible. Home grown pineapple would taste unbelievable I think ! Tom
Title: Re: new greenhouse planning
Post by: brian on December 09, 2015, 02:37:30 PM
Millet, insulating the southern wall is a very good idea.  I expect I will do this if practical.  I may have considerable choice in the direction of the greenhouse... would it make sense for the longer length to face north-south, or east-west?  I would think north-south would receive the most light in summer, but maybe not so much in winter (because of lower sun angle) when it is needed most.  I also may be able to build the greenhouse into a slope somewhat, so the rear wall could be partially underground and insulated in that way, or the whole thing could be a lean-to into a slope depending on the lay of the land.

Cory, yes I was thinking I may have a section for higher humidty and heat and grow some true tropicals.  I'm excited about this prospect.

Tom, rather than have multiple greenhouses I'm thinking of adding a polycarb wall or similar and having different sections as I mentioned above. 

I've done somewhat more research, I'm using GreenhouseMegaStore.com as a reference for now.  Most greenhouse kits are expandable, so I can start smaller and add space later if it isn't too difficult to expand.  However, it could be complicated if I need to get a new permit each time and add concrete footers or dig.   It is an option though.   There does not seem to be meaningful cost savings when buying larger sections at once versus adding sections over time, though perhaps freight cost if that is not included.

I ran through the heating calculators on www.littlegreenhouse.com (http://www.littlegreenhouse.com) and if I'm doing the calculations right the insulation advantage of 10mm versus 8mm polycarbonate may not be enough to justify the added material cost, especially if I may have to replace it every decade.   It looks like I definitely want polycarbonate, though, as PET film doesn't look sturdy enough and glass & acrylic are more expensive than polycarb for no clear advantage to me.

My current question that I have no good answer to is - How much ventilation is required to maintain reasonable midsummer temps?  It seems there are a few styles of ventilation:

natural: thermostatically controlled vents throughout the entire length of both walls and a ridge vent through the entire length of the ridge.  This is the design of the Ventmaster link above.
most expensive) 
fan-powered: vents on short ends of greenhouse, powered by fans.  Either a pair per end or the entire length of the short ends (minus doors)
fan-powered plus Active cooling:  (condensors, water-wall swamp coolers, heat pumps)

I am wondering how much is required in my climate.  I'm willing to do some labor twice yearly to simple remove wall segments or something to allow extra ventilation in summer if that somehow introduces huge savings versus a more complex ventilation option.  I was initially hoping that the cheapest option would suffice, but if I remember correctly Millet has both shade cloth *and* active cooling to maintain temps and he is in a similar climate to mine.  So perhaps he can offer advice on this portion.

Ventmaster design comes with PET sheeting roof but it looks like you could use PC instead
(http://cdn.greenhousemegastore.com/images/uploads/1850_6405_large.jpg)

Ranger Series powered fan vents on ends instead of side/ridge vents
(http://cdn.greenhousemegastore.com/images/uploads/1852_1824_large.jpg)

EDIT - found some great information on the PolyVent system the Ventmaster design uses:

"A second automated passive ventilation system is the Poly Vent from Poly-Tex Greenhouse Co. This system is a sidewall formed from a series of polyethylene tubes that are connected. When the tubes are inflated, the Poly Vent makes a tight-fitting, double-layer greenhouse sidewall. The inflation fan is controlled by a thermostat so when the greenhouse is warm, the fan switches to off and the wall opens; when the greenhouse is cool, the fan switches on and inflates the tubes thus closing the wall. This system has worked fine on research greenhouses at the South Farm for six years. Each wall is controlled by a separate thermostat, so staged control is achieved. This system is best for small greenhouses, up to 60-80 feet long; with longer greenhouses, wind and rain tend to move the tubes from their enclosure. This system is less expensive than fan ventilation, initially; but the tubes have to be replaced every 2-3 years so the system still has a recurring cost.

Contact us if you need an address for Poly-Tex. This has been a simple, reliable system in our use at South Farm. It is designed for straight sidewalls, but might work on a curved wall of a quonset. Remember, when the power goes off, the wall deflates and the greenhouse is wide open; this is quite a disadvantage during winter power outages! They do sell a battery back-up system."


On evaporative cooling:   Pennsylvania average summer afternoon humidity is 56% per http://www.currentresults.com/Weather/US/humidity-by-state-in-summer.php. (http://www.currentresults.com/Weather/US/humidity-by-state-in-summer.php.) 


Title: Re: new greenhouse planning
Post by: Millet on December 09, 2015, 09:49:34 PM
Personally, of the two greenhouses you show I would purchase the second one (Ranger Series powered fan vent)  My greenhouse has two fans (similar as shown in the picture) on the north end of the greenhouse, and two vents on the south end. The fans are capable of totally replacing the entire air volume inside the greenhouse structure (32-ft. wide X 72-ft. long X 11-ft. high) every one minute. Before building the greenhouse I would trench a 3 to 4 foot deep foundation trench around the entire greenhouse directly where the structure will sit, and insulate the trench so that the soil inside the greenhouse is insulated from the soil outside the greenhouse.  Doing so cause the entire greenhouse soil to become a heat sink reducing the heat expense throughout the winter months.  Also insulate the side kick walls. The little amount of light that the side kick walls bring, is not worth the extra heat that would be required if they were not insulated. Almost all commercial greenhouses are always build on a north/south orientation.  If you bild a greenhouse on an east/west ornamentation the sun bends greenhouse plants to the south.  Insulate the north wall.   In my greenhouse I also have removable insulation that covers the south wall at sunset and removes at sun rise. Do as you wish about the greenhouse roof.  I chose to use Teflon coated greenhouse grade double wall air inflated PET, which gives the highest R value.  It does reduce some light, but because the elevation here in Colorado where I live is 5,440-ft. the sun intensity here is extremely strong.  Using Teflon greenhouse grade PET, I normally replace the top about once every 5 years or so. It normally takes about 4 to 5 hours.

Millet
P.S. With that greenhouse you can plant your trees in the ground, giving you and your new wife (and the neighbors) all the citrus you and your neighbors could ever use.
Title: Re: new greenhouse planning
Post by: brian on December 10, 2015, 04:37:20 AM
Thank you Millet.   

I am surprised to hear you are using PET.  I imagined it would not survive the weather there.  Do you not get hail?  Any puncture issues?  Does it build up snow & ice?  I will certainly give this a second look. 

As far as insulation goes, many of the prefab kits come with PC end walls and side walls, with PET or PC options for glazing.  If the side walls and north walls will be insulated, I may simply build them out of plywood and foamboard insulation rather than adding foamboard overtop of more expensive PC, wasting its transparency. 

"In my greenhouse I also have removable insulation that covers the south wall at sunset and removes at sun rise"   -   Is this insulation inside or outside the greenhouse?  Some kind of rollup fabric?  Is this wall less insulated than the inflated PET roof?
Title: Re: new greenhouse planning
Post by: Millet on December 10, 2015, 12:10:32 PM
Brain, your using the three letters PET I assumed you meant Polyethylene film?   I'm not sure what the "T" stood for.  The roof on my greenhouse is two layers of 6-mil. The greenhouse grade has a Teflon covering on one said of the film.  This protects the film from the sun's degrading of the film.  Yes, we do get hail, but most bounces off.  They make a polyethylene 4" wide tape to cover any holes or cracks in the film .  The south wall insulation on my greenhouse is put up and removed manually by me.  It is made from 4' X 8' polyurethane aluminum one sided insulation board. It takes abut 5 minutes to put up and take down.  The average humidity for my location is 51% mornings 38 percent 5-pm afternoon.  Average daily humidity is 48%.  Evaporative greenhouse cooling works fine on 95 percent of the days. - Millet
Title: Re: new greenhouse planning
Post by: brian on December 10, 2015, 05:08:18 PM
Yes, by PET I do mean polyethylene film.  I will do a cost comparison on PET vs PC next time I do heating calculations, in terms of material cost vs heating efficiency.  Thanks for the information.

It sounds like fan ventilation plus evaporative cooling pads should be sufficient for me.  I expect I will go with this design. 

Title: Re: new greenhouse planning
Post by: Daintree on December 10, 2015, 10:49:05 PM

Heating:  I believe natural gas is the cheapest heat source at the moment.  Would make sense to allow some of the exhaust gasses to flow inside the greenhouse to add C02?  Obviously you would need some kind of sensors to detect dangerous pollutants or CO2/CO levels.  But my understanding is that natgas & propane can be very clean burning if properly maintained.   

Cooling:  my winter greenhouse gets above 115F in the summer when it is empty and the plants are all outside.  Is it possible to keep temperatures reasonable with only natural+fan ventilation?  It would certainly be possible to have a shade cloth either year-round or in the warmer months only.  I'm not sure how much air conditioning would cost but I imagine it would blow my budget entirely and I'd have to rethink the whole project.  It gets humid in summer here so evaporative cooling may not be effective.

Hi Brian!
Heating and cooling are two things I deal with a lot here in Idaho.  As far as heat, if you use an open flame gas furnace, the by-product is water vapor. This helps me with humidity in our dry winters, but adds no CO2.
As far as cooling in summer, the biggest help for me has been a shade cloth on a frame about a foot higher than the greenhouse.  Having it laying on the greenhouse just traps the heat.  The metal frame stays up all year, and I put the shade cloth on in late May and take it down in early September.  I use a lot of fans, plus the shade, and my indoor temps never get as hot as outdoors.  I also have tropical birds that live out there, so I am always very careful with air breath ability and temps.
Hope that helps!
Title: Re: new greenhouse planning
Post by: Millet on December 11, 2015, 04:01:10 PM
There are two types of shade cloths for greenhouses - Black Shade Cloth and Silvered shade cloth.  I have used both and place them directly on the greenhouse covering.   Personally, in all the years that I have been growing in a greenhouse I have never known a shade cloth causing additional heat inside the greenhouse.  The reason to use a shade cloth is to cool a greenhouse.  Of the two, I prefer the Silver net (Aluminized net).  It is called AluminNet and can be found using a simple Internet search. The black net blocks sunlight, while the AlumiNet both blocks sunlight and because it is silver colored it also reflects the sunlight away.  AlumiNet  comes in different weaves blocking out between 30 to 70 percent of the sun's light, I use the 30 percent shade  weave.  Between the shade cloth and evaporative cooling, I can keep the greenhouse at nice 80-F on a 100+ F sunny day. There is also a white liquid spray shade paint that is sold .  It is sprayed on in spring, and washed off in the fall. - Millet
Title: Re: new greenhouse planning
Post by: brian on December 11, 2015, 07:21:45 PM
Thanks for the information Daintree.  I will hold off on an evaporative cooling system until it proves to be necessary.  I am hoping shade cloth + ventilation will be enough.

However, I think you are mistaken about the CO2 emissions of burning natural gas.  This absolutely produces significant amounts of CO2.  You may be thinking about Hydrogen which only produces water vapor.  I am also thinking about putting birds in my greenhouse.  How does it work out for you?  I'd worry about them destroying smaller plants.   And if you are running an unvented heater with birds living inside and have no issues that is encouraging in terms of emissions safety.

(http://www.agiweb.org/education/energy/images/methane.png)
Title: Re: new greenhouse planning
Post by: brian on December 11, 2015, 07:41:31 PM
I double-checked my heating calculations.  It looks like maintaining a 55F min temp with average lows of 27.5F for five months will cost ~$50/mo to heat @32cents per 100cuft of natural gas, which is what my local gas company (PECO Energy) lists as the current price for gas.   This is cheaper than I expected.  Given this, the cost savings going as high as 16mm triple wall polycarbonate is only ~$8/mo would never pay off in the lifespan of the panels. 
Title: Re: new greenhouse planning
Post by: karpes on December 12, 2015, 06:50:26 PM
 Millet
  Have you noticed a decrease in heating cost? I would think that the fuel cost would be much lower now.
Title: Re: new greenhouse planning
Post by: Millet on December 13, 2015, 01:34:57 PM
Karl, yes the cost to heat the greenhouse is lower this year.  My greenhouse is heated by propane.  Last year propane was $1.90 per gallon, this year it is $1.09 per gallon. - Millet
Title: Re: new greenhouse planning
Post by: Millet on December 18, 2015, 11:59:49 PM
Two or three 20" box fans should be evenly placed between the north and south ends of the greenhouse near the ceiling to blow the hot air back down to the growing area.  Besides heating the plants, it lowers the temperature differential between the inside and out side temperatures at the roof's glazing. Without the fans, the air temperature at the greenhouse roof is quite warm, and the outside temperature is very cold during the winter.  The greater the temperature differential between the inside and outside, the faster the heat is lost to the outside.  Ceiling fans save a lot of money.  During the summer months leaving the ceiling fans off helps keeep the growing area cooler, by letting the heat raise towards the top of the structure.  - Millet
Title: Re: new greenhouse planning
Post by: Millet on December 19, 2015, 02:11:40 PM
I just read an article where a company started a "greenhouse" produce farm, using not actual greenhouses, but growing inside ship (freight) containers using  LED lights instead of the sun. I am always amazed at human ingenuity. - Millet.
Title: Re: new greenhouse planning
Post by: brian on December 19, 2015, 11:14:56 PM
Yes, I saw the mention of air circulating fans in many greenhouse planning docs, sounds like a requirement.

And I was also taking a step back and considering that large barn/shed insulated to R30 with grow lights would likely be far more efficient than heating and cooling a solar greenhouse.  Controlling humidity would be an issue, I assume.  Its an interesting thought.  Keeping containerized trees in a lighted basement would even work.  Doesnt seem like as much fun, though.  Being in a sunny greenhouse is a nice feeling.

So, after doing more research in my area it seems natural gas is not readily available.  Most homes use propane or heating oil.  Both cost around 2-3x what natural gas costs, so all of the sudden efficiency matters a lot to me.  My new working plan is a quonset roof of 8mm PC, and a silvered "bubble wrap" pool-cover type insulating blanket that can be rolled across the round roof automatically at dusk and retracted at dawn.  It would need a manual shutoff for when it snows.  Trapped moisture could become an issue but pool covers are generally treated to retard growth.  The silvered material would also block light, so I could activate grow lights at night without lighting up the neighborhood.  The south wall would be something like 16mm triwall PC, and insulated north wall and sidewalls (and foundation) as you reccomend.  My only concern is that a quonset roof will hold snow while a gothic or gable shape sheds snow easily.  My current greenhouse face sheds snow very efficiently.  I cant envision a solution for an automatic insulating blanket that would work on a pointed ridge roof.  If anybody has and ideas Id love to hear them.  Mounting the insulating blanket on the roof peak doesnt seem practical, and pushing a soft material against gravity doesnt work well.  Perhaps having a wire and pully that pulls a cover up each face could work.
Title: Re: new greenhouse planning
Post by: brian on December 19, 2015, 11:36:16 PM
Actually... Maybe having the insulation blankets roll horizontally instead of vertically across each side of the roof could work with a pointed roof.  They could be mounted on the north face where they wont be blocking light, and I can access them with a ladder on that side in case of jams/debris/snow
Title: Re: new greenhouse planning
Post by: Millet on December 20, 2015, 01:17:37 PM
For 14 years I worked for a greenhouse chemlical supply company.  I called on greenhouse operation all of the western United States.  In all cases greenhouse ceiling insulation blankets are always on the inside of the greenhouse, never on the outside.

https://www.youtube.com/watch?v=m4lw7-_gYAI (https://www.youtube.com/watch?v=m4lw7-_gYAI)

Millet
Title: Re: new greenhouse planning
Post by: brian on December 20, 2015, 04:39:23 PM
Thanks for the video.  It is interesting to see how the covering is applied high up in the greenhouse, rather than straight across as I have seen other examples of.  However, the R-value of such a covering seems like it would be low compared to the type of cover I am describing.  I'm wondering if it would be possible to do a similar design with a heavier material.  A thicker material would be hard to roll at anything other than a straight angle.  And going straight across horizontally wouldn't work if my sidewall height is low... around 4ft I am expecting.  It would cut off most of the ceiling space.
Title: Re: new greenhouse planning
Post by: Millet on December 20, 2015, 10:38:20 PM
The thickness of the covering has a lot to do with the climate of the area.  The one in the video  was in Turkey.  The coverings in Colorado are quite thick due to the cold winters, and the need for good insulation against heat loss. As you wrote, there are straight  coverings as well as ones shown in the video.  In all cases no coverings that I have ever seen were rolled, they are pulled in each direction like curtains. See the black metal peaces at the end of each curtain section (shaped like a "V"), they are what gathers the cover and folds it up like a curtain.  Anyway just an example of what is used in commercial greenhouse structures. Your future greenhouse will certainly be exciting, both for you and us to follow. - Millet
Title: Re: new greenhouse planning
Post by: brian on December 21, 2015, 05:29:53 PM
Ah, yes.  I looked into the thermal curtain systems your video describes.. it seems that the pocket of air trapped above the curtain may be more valuable for insulation than the material thickness itself.  The only downside of this type of system that I can see is that it appears very expensive... maybe $7-8k for the size I am looking at.  This is enough to make an insulated non-transparent structure w/ grow lights seem more attractive.  I don't think I can replicate this type of thing on my own, either.

So, I'm trying to find a way to get the best of both worlds... that is a bright, sunny, clear structure in daylight and an insulated blackout bunker at night.  I was brainstorming for a while and external insulating blankets seem like the only workable solution I can think of. 

Investigating pool covers and bubble insulation I came across the many articles explaning how bubble-wrap type radiant barriers have nearly no R-value, and the R-value advertised is derived almost entirely from the presumed air gap created by the material and not the material itself.  So, I was thinking of a flexible material that would have an actual R value.  The only thing that came up in my search is "K-Flex INSUL-SHEET" which is closed cell foam.  However, it looks very heavy and is expensive... as much as an internal automated curtain system just for the material itself.  The cheapest insulating material I'm aware of is spun fiberglass rolls/batts, the same as interior walls are insulated with.   Of course this isn't weatherproof.  Sooo.... my somewhat crazy idea is to sandwich a layer of 2.5" R13 (thinnest I can find) fiberglass between two layers of plastic, of which at least one is reflective/blackout/radiant, creating a pair of giant ~18'x48' insulating blankets that roll up either side of a gothic/gabled greenhouse.  It would require a small reel at the peak across the length of the greenhouse, and a large reel on each side to hold the blanket during daytime. 

Aside from the effort of creating the whole thing, the big problems that come to mind are:

1) Wind blowing the cover off.  I think with the correct design this will actually not be a problem because it will be taughtly strapped into place on either end and connected to reels
2) Moisture - mold growing on the underside of the blanket, or water penetrating the plastic cover soaking the fiberglass.  This would make it far heavier, drastically reduce R-value, pretty much ruin the design. 
3) Friction between the insulating blanket and the roof while it is raised/lowered.  I know from experience that polycarbonate panels are very slippery.  Combined with a textured plastic like the bubble-wrap style radiant barrier this may not be an issue.  The screws used to secure the polycarbonate roof to the purlins and join the panels would have to be rounded to avoid jagged edges that would catch the plastic as it moves across.  If the blanket is wet, however, it may not slide well at all. 

This could give an incredible R16.6 insulation factor (.06 heat loss factor) for the roof.   For comparison, plain 8mm twinwall polycarbonate is R1.6 (.62 heat loss factor) and 16mm triwall is R2.5 (.42 heat loss)

anyway I'm still thinking about this as I have tons of time before I would begin construction.  Here's a mockup of what I'm describing...

(http://i.imgur.com/l08TQEJ.png?2)

I calculated the blankets of this design to cost ~$550 each to make so ~$1100 total plus the cost of reels, motor, timer, etc.  If it worked it could pay for itself in one heating season.
Title: Re: new greenhouse planning
Post by: Mark in Texas on December 26, 2015, 02:59:16 PM
Here's mine, a Nexus Zephr.  10' columns, 18' peak, rainwater collection (later added).

(http://s9.postimg.cc/jgcuc3ayz/Greenhouse_At_Dawn_Setting_Moon.jpg) (http://postimg.cc/image/jgcuc3ayz/)

Am raising cados, mango, pineapples, citrus, sugar apple and the usual stuff like maters, herbs, etc.

ILink 800 controller, http://store.link4corp.com/igrow-800-greenhouse-controller/ (http://store.link4corp.com/igrow-800-greenhouse-controller/)   Locke 1 HP motors, Reznor propane heater, 4' tall guillotine wall vent on south wall, 2' rack and pinion on the roof.  Palram SolarSoft corrugated covering.  Here's a link - http://tropicalfruitforum.com/index.php?topic=7511.msg96609#msg96609 (http://tropicalfruitforum.com/index.php?topic=7511.msg96609#msg96609)

Secure the columns on top of an above ground concrete beam instead of in the ground or have them rusting at ground level like mine are now.

Cheers!
(http://s18.postimg.cc/4c9ydzwl1/Markwith_Beerin_Greenhouse032015_resized.jpg) (http://postimg.cc/image/4c9ydzwl1/)

Good luck with your new bride and project.
Title: Re: new greenhouse planning
Post by: Millet on December 26, 2015, 04:09:19 PM
Mark, nice greenhouse.  I think Nexus supplies Reznor heaters no matter what type of greenhouse you purchase from them. I have a Nexus Alpine greenhouse, it also came with a Reznor propane heater.  I installed an additional 250,000 BTU propane heater, so now I have two heaters in the greenhouse just in case one of them should go out on a cold Colorado night. One set at 50-F and the other at 55-F.- Millet
Title: Re: new greenhouse planning
Post by: Mark in Texas on December 26, 2015, 09:42:40 PM
Sounds good.  I let my lows go down to 34F.  I'm cheap. :)
Title: Re: new greenhouse planning
Post by: Millet on December 26, 2015, 10:16:14 PM
Mark nothing wrong with letting the greenhouse temperature get as low as possible.  It saves on the propane bill. Your giving up winter growth for lower propane bills. Besides  central Texas has many more warm daytime temperatures, and higher nighttime temperatures then does Colorado - Millet
Title: Re: new greenhouse planning
Post by: brian on December 26, 2015, 11:28:34 PM
That looks like a really nice greenhouse, Mark.  Do you have active cooling?  How does it handle the Texas summers?

When doing heating calculations I'm using 55F as the maintained temperature, however with my current setup I have my heaters set to 55F but they are undersized and allow the temperature to drop to ~35F when its below 0F outside.  I'd like to start growing actual tropicals with the new greenhouse so I'm trying to do all I can to have a reasonably high minimum temperature. 

From playing with various heating cost calculations it seems the largest controllable factor by far in heating costs is the target minimum temperature.  Dropping this by a small amount has a huge savings compared to using thicker glazing.  Decreasing overall surface area has a large effect too.
Title: Re: new greenhouse planning
Post by: Mark in Texas on December 27, 2015, 12:28:06 PM
Have 2 swamp coolers now.  Plan on installing flash nozzles run by a very high pressure (1,000 PSI) pump.  I hit over 100F often in the summer.

Don't get too anal about climate control.  It will all have to be tweeked come reality.  Mass plays a huge part too. 15 trees with large canopies store a lot of heat compared to a dozen tomato plants.   

You're right Millet.  This greenhouse stuff is a toy anyway.  Another one of my man caves.  ;)
Title: Re: new greenhouse planning
Post by: Millet on December 28, 2015, 11:54:41 AM
I remembered reading (about 10 years ago) about a double poly air inflated greenhouse insulation system where polystyrene pellets were blown into the two inch space between the double poly layers at night, thus filling up the space providing almost complete insulation, and then blown back out the next morning leaving the  root clear to receive the sun's light during the day.  The claim was a 90% heat savings.  Therefore, I tried to find the system on the internet.  Below is a link to how this was achieved. - Millet

https://etd.ohiolink.edu/rws_etd/document/get/osu1295548226/inline
Title: Re: new greenhouse planning
Post by: brian on December 28, 2015, 01:06:49 PM
This is an excellent idea, I am curious about their design.  Reading the document now...

I had wondered about adding additional layers of inflated PET to acheive 3x, 4x, etc.  but I imagine it is similar to having multiple layers of PC where you start to lose light transmission considerably. 

Title: Re: new greenhouse planning
Post by: brian on December 28, 2015, 01:49:10 PM
That's a really clever idea.  It sounds like their implementation had some problems.  The only potential improvements I can think of would be to use something like ping pong balls instead of styrofoam pellets for better flow, and to use a rollup/retracting "dryer exhaust" type tube instead of the zipper tubes they tried.  It seems it also takes a lot of tuning to get the flow just right and avoid plugs.  Finally, the biggest problem I can see for me trying something like this in a residential area is the possibility of millions of styrofoam bits spilling all over the neighborhood if something bursts.  That would make me very unpopular.

I'm trying to think of other similar designs where insulating material can be moved into place along the roof with pneumatics instead of pulleys & tracks.  The ability to store the insulating material outside the greenhouse is some kind of reservoir (instead of folded up, limiting its thickness) is a huge win.
Title: Re: new greenhouse planning
Post by: brian on December 28, 2015, 01:53:58 PM
Seeing as I have a bunch of leftover fiberglass rolls from my current greenhouse construction and various tarps, I am thinking of doing a mockup of the proposed thermal blanket design to see how well it slides up a polycarbonate face, especially when wet. 
Title: Re: new greenhouse planning
Post by: Mark in Texas on December 28, 2015, 02:14:35 PM
There's always unintended consequences.  I wonder if static electricity would stick those foam balls to plastic like glue.
Title: Re: new greenhouse planning
Post by: Daintree on January 04, 2016, 08:31:57 AM
Thanks for the information Daintree.  I will hold off on an evaporative cooling system until it proves to be necessary.  I am hoping shade cloth + ventilation will be enough.

However, I think you are mistaken about the CO2 emissions of burning natural gas.  This absolutely produces significant amounts of CO2.  You may be thinking about Hydrogen which only produces water vapor.  I am also thinking about putting birds in my greenhouse.  How does it work out for you?  I'd worry about them destroying smaller plants.   And if you are running an unvented heater with birds living inside and have no issues that is encouraging in terms of emissions safety.

([url]http://www.agiweb.org/education/energy/images/methane.png[/url])


Well, that just shows you how much I know about chemistry!

Of course, my greenhouse is not a tight construction so I don't have to have a vented heater.  I do know that the blue flame heater DOES make a lot of water vapor, which is great with our low humidity. Mine is 20,000 BTUs.

As for the birds, they do great out there (some have lived out there for 7 years).  I have nets under their perches (poop-catchers!) for MY comfort, and my seedlings live on racks that I have covered with cheap, green plastic fencing.  The poles that my vanilla orchids and Nigerian walnuts are on are also fenced in.  The green plastic fencing is easy to work with and blends in pretty well with the general "decor" of the place.
The birds do read Latin, and can count, however!  They only go for plants that have "edulis" or "deliciosa" on the tag, or that were particularly expensive to purchase…
Some bird species are more destructive than others, so shop carefully. Giving them something they are allowed to eat helps a lot.  Mine LOVE chia pets! 

You can see the furnace on the back wall in the picture.  Notice what looks like bbq racks on the front of the heater - that keeps the birds from exploring during the non-heating season.  They are cavity nesters, and are in to every nook and cranny in the place!  I am trying to build a fake tree for nesting, but I am on about failure #6 right now. They have to put up with unrealistic-looking bird houses right now.

It's an ecosystem that is tremendous fun, but always teetering on the brink of chaos.

I don't know why the shade cloth directly on the greenhouse held in heat, but it really made a HUGE difference to put it on a frame.  A friend here in town with a greenhouse had the same problem.  My guess is the size of our backyard greenhouses, compared to a commercial type of setup.  My ceiling height is only a little over 10 ft. Also, I don't have roof-top vents.  I have a 3 ft window on one end, and an exhaust fan at the top of the opposite end wall. 

Here is my granddaughter with one of my Bourke's grasskeets (anything she loves, she kisses.  My plants are also well-kissed!)

Cheers!
Carolyn

(http://s16.postimg.cc/7wpfcx8ch/Elly_and_Rainbow.jpg) (http://postimg.cc/image/7wpfcx8ch/)
Title: Re: new greenhouse planning
Post by: brian on January 04, 2016, 05:10:55 PM
This is great to hear, Daintree.  Glad things are working out so well for you.  I'd definitely like to keep a few birds in mine.
Title: Re: new greenhouse planning
Post by: brian on August 25, 2016, 09:57:34 PM
So I am moving forward with this project.  I decided to go with a significantly smaller greenhouse when my wife pointed out that the 30x48' design I was looking out had a bigger footprint than our house!  So now I am considering this one:
(http://cdn.greenhousemegastore.com/images/uploads/1843_1913_popup.jpg)

Because of the local township rules I need a 3ft deep foundation if its over 600sf, and only a 1ft foundation if its under 600sf.  This model comes in 18ft width and 4ft lengths so I'm going with either 32' (576sf) or 36' (648sf) depending on how deep I want to go.  The current question I have is how deep I should be insulating the ground for in-ground trees.  A quick google search says "Like most trees, the majority of the orange tree's roots are concentrated in the top 2 feet of the soil".   The International Residential Building Code specifies vertical insulation only 1ft deep to avoid freezing, but I'm shooting for a much warmer root zone.  At larger depths, a combination of vertical and horizontal insulation is called for.

So, the easier method would be to something like this with 18x32' greenhouse, 1ft deep foundation, 1ft of vertical and 1ft of horizontal insulation (minus the slab floor):
(http://www.homepower.com/sites/default/files/uploads/sidebars/9_SB_HP129_pg66_Johnston-5.jpg)

However, I'm going to have to rent a trench digging tool anyway, and I think they go down to 3ft.  So, it might not be much harder to do a 3ft than 1ft.  If this is the case I can just do 3ft deep vertical insulation along the foundation wall and the tree roots will be stuck inside the foundation anyway so I shouldn't need any skirt insulation.  This would let me build a slightly bigger 18x36'.  Increased concrete costs, minor increase in greenhouse cost

So... I'm thinking I may order the 36' length and see if I hit a bunch of rocks when digging.  If it looks sketchy I can skip the last 4' section and do the 1ft foundation.
Title: Re: new greenhouse planning
Post by: Mark in Texas on August 26, 2016, 09:52:19 AM
What brand?  Looks like my Dad's from Texas Greenhouses.

I would look hard at a Nexus. I have the 30X36' Zephr and love it. It's fully automated with roof and wall vents, iLink controller, two 1 HP Locke motors.

(https://s10.postimg.cc/f0w9i88xx/Greenhouse_3.jpg) (https://postimg.cc/image/f0w9i88xx/)

Millet, recently replaced the Palram SolarSoft85 with clear Lexan on the north roof.


(https://s11.postimg.cc/qb2hl8cm7/North_Wall.jpg) (https://postimg.cc/image/qb2hl8cm7/)
Title: Re: new greenhouse planning
Post by: brian on August 26, 2016, 10:30:58 AM
This is a Conley's Hobby House w 6mm dual-polycarbonate panels all around.  I'd prefer 8mm but they said it can't flex enough at the eaves. 

I did look at the Zephyr you have but it is a bit taller than I'm looking for.  Also, I'm wasn't sure how well natural ventillation would work out with inconsistent winds.  Glad to hear it does work for you!
Title: Re: new greenhouse planning
Post by: Mark in Texas on August 26, 2016, 10:50:02 AM
Conley's an excellent house and my first choice with high columns.  Never could get a 3rd party rep here in Texas to get it done so I switched to Nexus.  I wanted a tall roof cause I'm growing big trees like avocados, citrus and mangos.  My Reed avocado here is over 10' tall and this photo doesn't do it justice regarding the wide angle shot.

(https://s22.postimg.cc/3sitark65/Reed_Aug21.jpg) (https://postimg.cc/image/3sitark65/)


(https://s13.postimg.cc/5k4raywoz/Reed_June_2.jpg) (https://postimg.cc/image/5k4raywoz/)

BTW, I made a warranty claim to Palram for the roof SolarSoft85, griping about the loss of light transmission after 3 years.  Their specs said it came in at 76%.   In spite of folks in this biz warning me my claim "will never happen" they replaced the roof covering free which included a big expense of crating and shipping a 26' long crate.  Could not believe it! Now that's service!  It was actually Green Tek, a Palram rep that replaced it.


Title: Re: new greenhouse planning
Post by: brian on August 26, 2016, 11:19:45 AM
The one I'm looking at is 5.5ft at the edges (eaves) and 11.5ft at peak.   So, my plan is to put my most vigorous trees in the center and smaller ones along the edge.  Given my experience with temperate in-ground fruit trees, anything taller requires a ladder to pick and I'm just too lazy to use one so I prune me trees above this height.

I am planning to order through IGC (aka greenhousemegastore.com) as they seem to have a great reputation and their sales people have been very helpful.  I'm going to build it myself with some friends.   

Your trees look awesome.  I'm excited to get this set up.   
Title: Re: new greenhouse planning
Post by: Mark in Texas on August 26, 2016, 02:49:03 PM
Another reason why I used 10' columns is to get the heat off the trees.  You probably don't have to worry about summer heat but for very short periods. 

Good luck Brian!   Not to worry, that first orange will only costs $30,000!   ;D  I have lots of different tropical fruits including pineapples. They are pure sugar juice. 

(https://s14.postimg.cc/nln8x61q5/Pineapples_July31.jpg) (https://postimg.cc/image/nln8x61q5/)
Title: Re: new greenhouse planning
Post by: Millet on August 26, 2016, 02:59:23 PM
Brian, won't insulation on the outside of the walls get soaked?  Insulation that becomes soaked loses all insulation value.   Be absolutely sure you build all the greenhouse you need.  After the greenhouse is up it is to late.  I now wish  my 32' X 72' was 32' X 100'.   They fill up fast.   
Millet
Title: Re: new greenhouse planning
Post by: SusanB on September 21, 2016, 03:33:53 PM
Hi Brian,
I'm late to the discussion but I have a 21 x 36 Natural Greenhouse that you were first looking at.  We like it quite a bit except for some minor drawbacks. 
1).  It's big.  I made a mistake calculating, I looked at the plants in our house (8ft ceiling) and then decided to go with the 8 foot sidewalls.  Our land wasn't as level as I thought, so they had to build a wall for the GH to sit on.  So, it is TALL.
2) We put it up ourselves except for the initial wall and most of the roof polycarbonate.  We finally rented a cherry picker and some handymen and it was very easy then.
3)  It does cost a lot to heat.  I don't remember what we kept it at the first winter, maybe as high as 70, but it cost $2000 for the propane.  We put in a wood stove that does most of the heating now.  We get 1 tank load a year, about $500 depending on prices.   And no, the stove does not affect the plants at all, although they did get a bit sooty at times.
4) The inflatable sidewalls work great until they don't.  The back up batteries do fine for about 2 hours, but you should have a generator just in case of longer power outages. 
5) Invest in a concrete floor if you can.  We live on a rocky clearing where there is no dirt or grass, and a lot of dust.  The dirt floor of the GH also makes a lot of dust.  This gets on the inside vents, walls, and parts.  We've never had problems with the 2 fans, but we have had blowers go out.  My husband was thrilled to replace them at 2 am with snow coming in the vents.  And yes, the plants were fine.
6) If you have regular breezes, the natural ventilation works great.  We get very little wind here and in the summer the greenhouse is super-hot, even with all the vents and doors open.  Having grass around the GH would probably help a bit with that, too.   

I've tried to load a photo but not sure if it will go through. 
Title: Re: new greenhouse planning
Post by: Millet on September 21, 2016, 09:19:46 PM
Susan, have ever given thought about investing in a shade cloth to cool the greenhouse during the summer..   There is a great one called Aluminet which is a silver sideded net that reflects much of the sun's radiation away.  I use a 30% shade net. Thanks for joining the forum.  Take care. - Millet
Title: Re: new greenhouse planning
Post by: SusanB on September 22, 2016, 12:04:04 AM
Hi Millet, nice to be back!  It doesn't matter.  with our rock it's like living in the middle of a concrete parking lot, the ground doesn't absorb the heat, just reflects it up.  I have a 20 ft shadecloth (black) on the outside which does help a bit in the winter.  And I do have a couple of trees that live in there year around, 2 Ceiba speciosa and a Bursera simbaruba (probably spelled wrong) that do OK with the temps getting 120 or more.  Which I guess is only 30 degrees warmer than the 90 degrees we had for so much of the summer so it's to be expected.  Citrus table to the right.
(http://s9.postimg.cc/y4362ckuz/DSC02781.jpg) (http://postimg.cc/image/y4362ckuz/)
Title: Re: new greenhouse planning
Post by: brian on September 22, 2016, 07:56:39 AM
Brian, won't insulation on the outside of the walls get soaked?  Insulation that becomes soaked loses all insulation value.   Be absolutely sure you build all the greenhouse you need.  After the greenhouse is up it is to late.  I now wish  my 32' X 72' was 32' X 100'.   They fill up fast.   
Millet

Millet, the rigid foam insulation I'll be using on the foundation exterior is impermeable so this should not be a problem.  This type of insulation foundation design is specifically allowed by the International Building Code and recommended for energy efficiency and material savings.

As for size, I would like to have gone larger but the building regulations would have made it prohibitively expensive for me.  And actually, can't you simply expand yours?  They're generally sold in 4-6ft increments.  I imagine if you could disconnect the exterior wall during mild weather and add a few sections?
Title: Re: new greenhouse planning
Post by: brian on September 22, 2016, 08:08:23 AM
Hi Brian,
I'm late to the discussion but I have a 21 x 36 Natural Greenhouse that you were first looking at.  We like it quite a bit except for some minor drawbacks. 
1).  It's big.  I made a mistake calculating, I looked at the plants in our house (8ft ceiling) and then decided to go with the 8 foot sidewalls.  Our land wasn't as level as I thought, so they had to build a wall for the GH to sit on.  So, it is TALL.
2) We put it up ourselves except for the initial wall and most of the roof polycarbonate.  We finally rented a cherry picker and some handymen and it was very easy then.
3)  It does cost a lot to heat.  I don't remember what we kept it at the first winter, maybe as high as 70, but it cost $2000 for the propane.  We put in a wood stove that does most of the heating now.  We get 1 tank load a year, about $500 depending on prices.   And no, the stove does not affect the plants at all, although they did get a bit sooty at times.
4) The inflatable sidewalls work great until they don't.  The back up batteries do fine for about 2 hours, but you should have a generator just in case of longer power outages. 
5) Invest in a concrete floor if you can.  We live on a rocky clearing where there is no dirt or grass, and a lot of dust.  The dirt floor of the GH also makes a lot of dust.  This gets on the inside vents, walls, and parts.  We've never had problems with the 2 fans, but we have had blowers go out.  My husband was thrilled to replace them at 2 am with snow coming in the vents.  And yes, the plants were fine.
6) If you have regular breezes, the natural ventilation works great.  We get very little wind here and in the summer the greenhouse is super-hot, even with all the vents and doors open.  Having grass around the GH would probably help a bit with that, too.   

I've tried to load a photo but not sure if it will go through.

Great to hear others experience with this, thank you.

My ground is a bit sloped also, so one side of the greenhouse will be about 3ft taller than the other.  This puts it to about 14ft which isn't too bad for me.   I had done a lot of heating cost calculations before I started.  When house hunting with my wife I specifically looked for natural gas availability because natural gas is something like half the cost of propane, or better!   Previously in my old improvised greenhouse I was heating with electric space heaters which even with a off-peak rate was pricey.

You brought up a very very good point I hadn't thought about... back up power.   I bought a back up heater but I believe it still needs electricity.  I will have to look into this.  I think a back up battery might be sufficient as the electrical draw for a gas heater is likely very small.

And as for dirt/dust... I agree with you it could be a problem so I was planning on planting grass or any kind of groundcover between trees. 

For ventilation... I have been meaning to investigate weather the added CO2 from allowing gas exhaust into the greenhouse would be beneficial or a negative because of the small amount of pollution that comes along with it.  The heaters I purchased are vented outside but I could always introduce a leak if I wanted to allow some exhaust in.  I am thinking I shuold get carbon monoxide detectors regardless.
Title: Re: new greenhouse planning
Post by: brian on September 22, 2016, 08:12:32 AM
Today the foundation excavation will be complete and I will start building concrete forms for the foundation.  The actual greenhouse kit won't be delivered for a few weeks as Conleys manufactures them to order so they are still cutting it.
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 22, 2016, 08:26:10 AM
Happy to hear it's coming along. Good luck!
Title: Re: new greenhouse planning
Post by: SusanB on September 22, 2016, 09:11:01 AM
Brian, how exciting!  I can tell you have put a tremendous amount of thought and work into it.  I really like the greenhouse you've chosen, when we bought ours the options were pretty limited, not many styles between small home gardener and professional. 

I'll have to go back and read through this thread more thoroughly. 

My plants are all in pots, although I've cut out the bottom of some pots to let them root through into the ground, after they took that route themselves, through the holes in the bottom of the pots.  The Ceiba and a few cactuses grow this way, some of the cactuses are at the edge of the greenhouse so I worried about them getting cold feet.  My guys did not do a good job on the base, it's basically a wooden wall with a little insulation tacked to it. 
I can feel that the bottom of the gh is cooler, but it hasn't seemed to affect anything so far.
Title: Re: new greenhouse planning
Post by: brian on September 22, 2016, 11:15:02 AM
Until next fall I am keeping all plants in containers.   Once I've seen how well I can maintain temps on the coldest and hottest days of the year then I will start planting in ground. 

I'm planning to take some temperature measurements in the center and edges of the greenhouse on cold days to see how low it gets.  The foundation will be 2ft down and insulated that far so I expect it should stay reasonably warm.  If it can't maintain at least 55F I will likely dig again and insulate further next year.

Looking at the excavation I can see that below a few inches of topsoil my yard is all heavy, heavy clay.  I think I will be amending compost or peat in. 
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 22, 2016, 02:05:43 PM

Looking at the excavation I can see that below a few inches of topsoil my yard is all heavy, heavy clay.  I think I will be amending compost or peat in.

Never amend heavy clay backfill with anything when planting.  Here's the logic - https://puyallup.wsu.edu/wp-content/uploads/sites/403/2015/03/soil-amendments.pdf
Title: Re: new greenhouse planning
Post by: brian on September 22, 2016, 02:49:31 PM
I'm talking about doing the equivalent of a raised bed.

To be clear, the current state of the greenhouse interior is a slight slope of clay soil with grass lawn on top, covered with a huge mound of dirt from excavation.  I can either remove the dirt, level it out, or maintain the slope inside the greenhouse.  I'm thinking the irrigation water will tend to pool to one side if I maintain the slope, so it likely makes sense to level it out.  If I'm moving all this dirt around it would be feasable to add some organic matter evenly throughout.  For example, if there's 2ft deep of insulated soil in the 18x32 perimeter, thats 1152cu ft or 42.6cu yd.  So, if the clay soil is 1% organic matter, adding eight $10 3cf-packages of peat moss would push it above 5%. 
Title: Re: new greenhouse planning
Post by: Daintree on September 27, 2016, 10:47:45 AM
Be sure and post pictures if you can - I love to see what folks are building and how work is progressing!!!

Carolyn
Title: Re: new greenhouse planning
Post by: brian on September 27, 2016, 01:00:05 PM
Right now I only have an exciting ditch!

(http://i.imgur.com/3thEIRR.jpg)


I hired a local excavator to dig foundation and service trenches.  I'm starting on concrete forms this week.
Title: Re: new greenhouse planning
Post by: Millet on September 27, 2016, 10:30:00 PM
brian, when you sold your old house did the new buyer like the attic greenhouse? In other words was it an asset or a liability?  - Millet
Title: Re: new greenhouse planning
Post by: brian on September 28, 2016, 12:32:38 PM
My brother lives in my old house now, I haven't put it on the market. 

However, I am planning to revert the old greenhouse back to a normal roof/attic once the new one is vetted.  I'll ask a few real estate agents what they think but I expect the answer will be that it will be easier to sell without it. 
Title: Re: new greenhouse planning
Post by: cory on September 28, 2016, 09:44:08 PM
It would be interesting to know what the market thinks.  I would like a sunny room like that.  Maybe an artist might like it for a studio or someone would like it for a bright craft or workshop.  Maybe another gardener will like it.  I have been thinking of adding skylights to my garage roof.  Anyway, I don't think I would remove the "glass" roof until you test the market for it.  It is quite unique.
Cory
Title: Re: new greenhouse planning
Post by: Tom on September 28, 2016, 09:52:33 PM
I agree that I hope you can leave the improvement as is. Very unique and seemed very well done. I enjoyed reading about it a while back on the other forum. That data might be lost forever. I haven't been able to log on for weeks (or months). I'm glad Millet got this in place when he did !!
Title: Re: new greenhouse planning
Post by: brian on September 29, 2016, 09:36:56 AM
Did anybody make a backup of the old site?
Title: Re: new greenhouse planning
Post by: Daintree on October 02, 2016, 07:00:33 PM
Right now I only have an exciting ditch!
I hired a local excavator to dig foundation and service trenches.  I'm starting on concrete forms this week.

Actually that really IS exciting!  My greenhouse is much smaller (500 s.f), but I dug the ditch by hand, then filled it with gravel by hand, then me and my mom (in her 70's at the time), hauled all the cinder blocks for the foundation, using her little Toyota truck.

So yeh, that little excavator is WAAAY cool!!!
Title: Re: new greenhouse planning
Post by: LaCasaVerde on October 22, 2016, 05:19:26 PM
Loved reading this post so far.
side note:
I read earlier in the post about heating requirements/costs
Ive used this calculator for my heating needs and expense calculations for my greenhouse. May  come in handy:
http://www.littlegreenhouse.com/heat-calc.shtml (http://www.littlegreenhouse.com/heat-calc.shtml)
Title: Re: new greenhouse planning
Post by: brian on October 22, 2016, 09:19:51 PM
Yup, that's what I've been using LaCasaVerde.   I hope it is reasonably accurate.
Title: Re: new greenhouse planning
Post by: Millet on October 22, 2016, 09:58:08 PM
As I have mentioned before, I use 10 black plastic 55-gallon drums lined in a row as greenhouse benches.   The drums are filled with water which totals 551-lbs. of water per each drum.  The water heats up during the day, and cools at night.  It takes one BTU of heat to raise 1-pound of water one degree, or reversibly, when 1-pound of water loses one degree of heat it gives off 1-BTU of heat to the greenhouse.  The 10 barrels used to make a greenhouse bench, contain 5,510-lbs. of water.  Lets say when night comes the water in the barrels is at 66 degrees, over night the water has cooled down to 57 degrees.  That means the watered cooled by 9-degrees. Therefore, the total weight of water in the 10 barrels (5,510-lbs.) gave of 59,590 BTU's of FREE heat into the greenhouse.  I have one hundred 55-gal. drums in my greenhouse. Six benches, plus the sides and  ends are lined with barrels.  One added note, plants setting on top of the warm drums grow extra well through the long cold low  light winter season. - Millet
Title: Re: new greenhouse planning
Post by: brian on October 23, 2016, 04:02:16 PM
I'm thinking of doing water barrels also, though I have more limited space as my greenhouse isn't nearly as large.
Title: Re: new greenhouse planning
Post by: brian on October 23, 2016, 09:37:10 PM
Actually, because my greenhouse will essentially contain 2-4ft of insulated dirt, it might have a large heat holding capacity on its own.
Title: Re: new greenhouse planning
Post by: Millet on October 24, 2016, 07:44:32 PM
Brian the greenhouse dirt floor in my greenhouse is also insulated from the outside. My greenhouse is at 5,440-lb. elevation.  The air here in Colorado is thin, so it heats up quickly during the day, due to the strong sunlite raditation at this elevation.  However, it also rapidly cools after sunset.  At this time of year (late October), we have warm days 75+-, but night temperatures fall into the 30s, even one night at 25-F.   Therefore, I changed the setting on the greenhouse exhaust fans so that they don't come on until the greenhouse reaches 95-F, so the water barrels,greenhouse floor, and objects inside the greenhouse heats up, thus radiating more heat and for a longer time back into the greenhouse at night. - Millet
Title: Re: new greenhouse planning
Post by: brian on October 24, 2016, 08:13:17 PM
Perhaps the heat capacity of the soil isn't as much as I'd hoped.  I am planning to take soil temperature readings until I have a good feel for what to expect.  Do you have a concrete foundation?  I'm wondering if that will also hold a significant amount of heat.
Title: Re: new greenhouse planning
Post by: Millet on October 28, 2016, 09:17:53 PM
Beneifits Of A Retractaable Greenhouse Roof - Millet

http://www.freshplaza.us/article/6604/Video-Benefits-of-retractable-roof-structure (http://www.freshplaza.us/article/6604/Video-Benefits-of-retractable-roof-structure)
Title: Re: new greenhouse planning
Post by: Millet on October 30, 2016, 09:54:39 PM
How is the new greenhouse coming along? - Millet
Title: Re: new greenhouse planning
Post by: Mark in Texas on October 31, 2016, 09:56:30 AM
Beneifits Of A Retractaable Greenhouse Roof - Millet

[url]http://www.freshplaza.us/article/6604/Video-Benefits-of-retractable-roof-structure[/url] ([url]http://www.freshplaza.us/article/6604/Video-Benefits-of-retractable-roof-structure[/url])


I looked for such a design on a small scale greenhouse with no luck before getting the Nexus Zephyr.
Title: Re: new greenhouse planning
Post by: brian on October 31, 2016, 02:14:54 PM
The foundation construction turned out to be far more complex than I anticipated.  I had spoken to some friends with concrete experience prior to starting but their experience was with pouring slabs which is much simpler than walls.  I had to spend a ton of time researching proper concrete form design to ensure they won't burst.  I'm getting close to being able to do the concrete pour.  The weather is still nice but winter is rapidly approaching.  If I don't get it done quick I'll have to resume in spring. 

In retrospect if I'd hired out the foundation it would only have been a bit more expensive than doing it myself.  It sure is a learning experience.  I have a handful of people to help me assemble the structure once the foundation is in place.  The greenhouse kit should be delivered in the next few days.  It took 6+ weeks to manufacture.

I put my trees in my old greenhouse for now, so the only urgency is that I hate having incomplete projects. 
Title: Re: new greenhouse planning
Post by: brian on October 31, 2016, 02:19:02 PM
From my calculations heating the greenhouse air should be reasonably affordable because natural gas is dirt cheap.  A lot of the efficiencies I though I'd need likely aren't actually cost effective with a fuel source this cheap.

I'm not sure about the ground temperature, though.  I won't really know until I get there. 
Title: Re: new greenhouse planning
Post by: forumfool on December 26, 2016, 07:14:37 PM
Bump.

Nice thread. Any update?
Title: Re: new greenhouse planning
Post by: brian on December 28, 2016, 11:45:12 AM
I got about 80% done the concrete forms before it got too cold to work outside  :-(   

I am now stuck waiting until spring to resume.   All my trees will have to remain in the old garage-attic-greenhouse at my old place until then. 


Title: Re: new greenhouse planning
Post by: forumfool on December 29, 2016, 08:00:05 PM
Zone 6 winters brrrrr.....

Well, you'll have all spring-fall to complete your project next year. Good luck on it. Looking forward to any updates...
Title: Re: new greenhouse planning
Post by: brian on July 23, 2017, 08:45:38 AM
Took a brief hiatus to have a baby.  Resumed work starting in early summer.   It took a ridiculous amount of effort to build the concrete forms.  If I was restarting from scratch I would instead use masonry block or rented forms instead of building my own.  Yesterday was concrete pour day, forms held strong.   Next steps are to pull and stack the form wood, insulate the foundation, level the dirt inside, backfill, run utilities, then assemble the greenhouse itself.   The greenhouse kit looks extremely well manufactured.

(http://i.imgur.com/EIQGiaf.jpg)
(http://i.imgur.com/iPYJyMv.jpg?1)
(http://i.imgur.com/VvM1TCi.jpg)
(http://imgur.com/EICGBQN.jpg)
(http://i.imgur.com/wOH7gz0.jpg)
(http://i.imgur.com/Jmo95B9.jpg)
(http://i.imgur.com/fhX7zmF.jpg)
(http://i.imgur.com/zN42uu8.jpg)
(http://i.imgur.com/CwL2U4M.jpg)
(http://i.imgur.com/DOcmc41.jpg?1)
(http://i.imgur.com/QQnAuPp.jpg)
(http://i.imgur.com/BfmFcBG.jpg)
(http://i.imgur.com/loUcu1P.jpg?1)
Title: Re: new greenhouse planning
Post by: Millet on July 23, 2017, 11:19:46 AM
First and foremost, CONGRATULATIONS on the new baby.  The baby will be a great and wonderful adventure for both of you.  Brian, it is really nice seeing you on the forum again.  I was thinking about you and your new greenhouse just the other day.   Looking at your pictures I was stunned on how much work it was just to put in the foundation forms.   When I built my greenhouse,  which is a 11-foot high hoop house there was much less items to put together.  Your greenhouse is going to be state of the art.  I know all of us on the form are excited to read about the progress as you post along the way the construction of the structure.  Nice seeing you again.  The best of luck.
Title: Re: new greenhouse planning
Post by: Susanne42 on July 23, 2017, 05:12:02 PM
Oh my goodness. Brian that looks just impressive and awesome. We (husband and I ) are thinking about putting up a greenhouse in three to four years too. Needs to be sturdy as we can have really heavy storms. No clue where to start but following you will be fantastic. Congratulation to your new baby. :)
Title: Re: new greenhouse planning
Post by: Citradia on July 23, 2017, 08:16:46 PM
Congratulations on the new baby, Brian! Good for you; building a greenhouse in zone 6 is the best way to grow citrus with less muss and fuss in the long run. I wear myself out running around covering and uncovering trees 6 months out of the year.
Title: Re: new greenhouse planning
Post by: cory on July 23, 2017, 11:49:23 PM
Congratulations on your new baby Brian.  I look forward to reading and seeing pictures as your greenhouse building progresses.  Very interesting so far.

Cory
Title: Re: new greenhouse planning
Post by: brian on July 24, 2017, 07:42:10 PM
Thank you for the kind words. 

I'm really happy that things are moving along well now.  I was worried for a while that my foundation plan wouldn't work and I'd have to restart from scratch.  Susanne, if you build a similar greenhouse I definitely recommend the same manufacturer (Conley's) as they have engineered designs for various wind and snow loads. 

I took some time off from work this week.  Started stripping the forms off today to get a look at the wall.  There's a few air bubbles where the concrete didn't settle but I'm going to patch them, should be okay.   
(http://i.imgur.com/qLxPgOd.jpg?1)
Title: Re: new greenhouse planning
Post by: Tom on July 24, 2017, 08:42:31 PM
brian, your greenhouse looks awesome. It's going to be great. Congrats on the wife and new baby/boss ! Tom
Title: Re: new greenhouse planning
Post by: brian on July 28, 2017, 07:11:14 PM
Thanks, Tom!

I've started insulating and backfilling.  Two sides done.  It takes a while to get the foam cut, glued, clamped, and then spray foam in the gaps... then tape.  The backfilling is a breeze in comparison as the dirt only has to move a few feet.   I'm thinking I will stucco the foam above ground.

(http://i.imgur.com/6dioqLY.jpg?1)
Title: Re: new greenhouse planning
Post by: Millet on July 28, 2017, 08:33:05 PM
That insulated foundation just made the entire greenhouse floor a heat sink. On a sunny day it will store a lot of heat and release it into the greenhouse during the night. .
Title: Re: new greenhouse planning
Post by: Mark in Texas on July 29, 2017, 10:23:01 AM
Wow, NICE job!!!!!!!!  Lot's of fine thought and work went into that.  What brand?

Being that we occasionally get down into single digits I can empathize with your dreams and considerations.  Took me 5 years but we're now enjoying and giving away the best Zill mangos (just grafted 7 new ones which took), avocados, pineapples, cherimoya, rollinia, citrus, maters.  You're gonna have some fun!!!!!!!!!!   :D

All my trees are in bottomless RootBuilder pots which I see you use.

Mark
Title: Re: new greenhouse planning
Post by: brian on August 31, 2017, 11:18:49 AM
I stucco'ed the outside of the foam.  I'll likely do another coat in the future, but its enough to protect the foam from scratches and dings. 
(http://i.imgur.com/SySdVlF.jpg)

Set up a frost-proof spicket.  In theory the greenhouse will never freeze but i'd rather take this extra step just in case.  Frost line is 3ft deep here, I had to hand dig out a foot of dirt after rain collapsed the trench in somewhat.
(http://i.imgur.com/RRJnKm1.jpg)
(http://i.imgur.com/HdxE6s2.jpg)
(http://i.imgur.com/Sz4Nath.jpg)

My brother and I assembled the structure legs and attached all the purlin fittings.  I had to chisel-level the concrete around the anchor bolts a bit where it was rough.  I think we are ready to actually start putting the frame up.
Title: Re: new greenhouse planning
Post by: Millet on August 31, 2017, 11:57:00 AM
Excellent, excellent, excellent work.  You could go into the greenhouse building business.  Thanks for the up date. exciting.
Title: Re: new greenhouse planning
Post by: brian on August 31, 2017, 12:13:49 PM
Excellent, excellent, excellent work.  You could go into the greenhouse building business.  Thanks for the up date. exciting.

Hah I suggested that to my wife.  She wasn't happy  :)
Title: Re: new greenhouse planning
Post by: brian on August 31, 2017, 12:22:10 PM
...  What brand? ...

Mark

This is a Conley's "Hobby House".  Given the date on the instructional video they've been making it since 1999.  So far everything is going together nicely.  If it wasn't for the huge effort to do the foundation I think it would have been a quick project.
Title: Re: new greenhouse planning
Post by: brian on September 15, 2017, 08:57:33 PM
Framing is nearly done. 
(https://i.imgur.com/rlaxYTn.jpg?1)
(https://i.imgur.com/XKugam3.jpg)
(https://i.imgur.com/Ng3xlCw.jpg)

Title: Re: new greenhouse planning
Post by: Millet on September 15, 2017, 09:29:55 PM
Thanks for the up date.  It is exciting to me and I'm sure the other members enjoy it as much as I.  You and your crew are doing an outstanding job.  You will enjoy that greenhouse for years to come.  Greenhouses really give a break from the winters.  You can go in on a cold snowy day and enjoy flowers, trees, fruit, and the warmth. Thanks again.
Title: Re: new greenhouse planning
Post by: raggashack on September 16, 2017, 07:56:33 AM
very nice work so far, now that is a real greenhouse, not the garbage amazon is selling :)
Title: Re: new greenhouse planning
Post by: forumfool on September 16, 2017, 10:04:29 AM
Was thinking about this project the other day and decided to open the citrus forum to look for an update. Glad I did!
Looks great, keep us posted with project.

Are you planting in ground?
Any heat options going underground?

This looks very nice looking forward to future posts. (Congrats on baby! Have a 3 month old myself :)
Title: Re: new greenhouse planning
Post by: cory on September 17, 2017, 12:43:25 PM
It's coming along nicely Brian.  I always look forward to your updates.
Cory
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 19, 2017, 10:31:09 AM
Beautiful job!  Good that you have a tall roof and columns.  That will come in handy when you get 10' avocado trees like I've grown into using bottomless RootBuilder pots.

Title: Re: new greenhouse planning
Post by: brian on September 19, 2017, 11:15:11 AM
Thanks, all.   Its still moving along.  I have about 14ft of vertical space in the center, and maybe 10ft at the edges

Forumfool, yes I'm planting in-ground.   I might do the bottomless rootmaker containers as Mark mentioned.   I have a large amount of rootmaker material already so this could be a good use for it.   I'll have to think about this.
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 19, 2017, 05:00:02 PM
Thanks, all.   Its still moving along.  I have about 14ft of vertical space in the center, and maybe 10ft at the edges

Forumfool, yes I'm planting in-ground.   I might do the bottomless rootmaker containers as Mark mentioned.   I have a large amount of rootmaker material already so this could be a good use for it.   I'll have to think about this.

Have been harvesting these exceptional Reed avocados since June.  Wife is in the middle.  Empty pot gets an El Bumpo cherimoya.

(https://s26.postimg.cc/jq2yre3kl/Nancy_Reed.jpg) (https://postimg.cc/image/jq2yre3kl/)

2014, adding panels to expand the pot size of this Moro blood orange.  Large white roots have rooted into the ground.

(https://s26.postimg.cc/d0wfbdi8l/Moro_Repot_June2014.jpg) (https://postimg.cc/image/d0wfbdi8l/)

Only way to go if they're in a permanent place.
Title: Re: new greenhouse planning
Post by: Susanne42 on September 19, 2017, 06:15:00 PM
Mark what is the height of your greenhouse?
Title: Re: new greenhouse planning
Post by: Millet on September 19, 2017, 06:45:13 PM
I see you use the 100-ft. RootMaker extended rolls to make your pots.
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 20, 2017, 09:59:52 AM
Mark what is the height of your greenhouse?

18' peak, 10' columns.

Yes Millet, the permanently installed trees are in RootBuilder - avocados, mangos, citrus.  Land is a hard calcareous clay loam which I dusted with sulfur and slightly fractured with fork before putting down the pot system.

Newly grafted cocktail mango, second flush of leaves, 4 Zill varieties is in the foreground, Reed in the back, right pot will get an El Bumpo cherimoya, pot on the left is my Frankencado - Sir Prize, Holiday, Pinkerton and Ardith.

(https://s26.postimg.cc/yvqomwck5/Cocktail_Mango_Sept13.jpg) (https://postimg.cc/image/yvqomwck5/)
Title: Re: new greenhouse planning
Post by: brian on September 20, 2017, 10:55:13 AM
Mark, what soil do you use in the containers?  Do you ever change it or is it permanent? 
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 21, 2017, 10:02:58 AM
Mark, what soil do you use in the containers?  Do you ever change it or is it permanent?

Use whatever I stockpile....and hell no, aint about to change it!   ;D

About 50/50 organics/inorganics - either or, neither or.....peat moss, pinebark, compost, bulk pile of builder's sand, coarse vermiculite.  Handful blood meal, topped off with a slow release encapsulate food 18-4-9 with micros.  Dump all this stuff on a carport floor and mix with my tractors bucket.

I mulch the pots with a thick layer of their own leaves and pine needles.  A thick mulch is a must for avocados.

(https://s26.postimg.cc/wvwcdsql1/Pickering_Mango_Aug.jpg) (https://postimg.cc/image/wvwcdsql1/)
Title: Re: new greenhouse planning
Post by: Susanne42 on September 21, 2017, 10:21:57 AM
Oh my goodness do they look yummy.
Title: Re: new greenhouse planning
Post by: brian on September 21, 2017, 10:51:38 AM
Mark, do you know roughly how much sand you are using?   I know if I don't change my container soil regularly it becomes thick as the mulch breaks down.  However, if moving the containers is no longer necessary I was thinking of using a gritty mix that provides drainage that won't break down over time.   

My other concern is my hard water.   I expect I'll need to collect rain water or get a reverse osmosis system to avoid calcium accumulation.  A RO system would let me use misters which would help with cooling in summer (with hard water the jets would clog quickly) but I'm not sure how much it would cost to operate. 

Current state:
(https://i.imgur.com/VndhY1c.jpg)
Title: Re: new greenhouse planning
Post by: Susanne42 on September 21, 2017, 02:48:37 PM
Brian will you only grow citrus in there? Any idea how many trees you can fit in there?
Title: Re: new greenhouse planning
Post by: brian on September 21, 2017, 03:42:04 PM
I will likely grow some other tropical fruits also.   I'm not really sure how many trees I will have because it depends how large they grow.   I am thinking of having maybe a dozen larger trees and some smaller containerized ones around the edges or hanging from the ceiling.  Right now I have about forty containerized fruit trees which won't all fit as they grow.   I am planning to pick my favorite of each fresh-eating type and get rid of the rest, and keep small lemon, lime, etc. for cooking.   I have so many trees because most of the fruit I can't obtain any other way, so I have no way to try it than growing it myself.   A lot of varieties are clearly inferior to others, so not much reason to keep both.   
Title: Re: new greenhouse planning
Post by: forumfool on September 23, 2017, 09:26:14 AM
Once threat of frost has past the roof is a liability as you mention by trying to keep it cool. What not try double poly for roof and roll it up in summer?

Like this:
https://www.youtube.com/watch?v=sj0bTU5Fs2o (https://www.youtube.com/watch?v=sj0bTU5Fs2o)
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 23, 2017, 10:18:31 AM
Mark, do you know roughly how much sand you are using?

Too much cause moving it from tractor's bucket to inside the greenhouse gets old real quick!  If I had to guess it's about 30% sand and 30% coarse vermiculite or perlite, the rest organics.  Even after 5 years the big pots drain really well.

I started off using well water which is very hard, TDS over 800 ppm, bicarbs of Mg and Ca. Neutral pH though.  I now collect rainwater and use a cheap pump.  Trees love it. 

Speaking of trees, I'm VERY careful about my real estate, actually there's a bunch of wasted space but knowing that avocado trees grow big I give them plenty of room.  I have 4 avocado trees, 3 citrus, 3 mango and a bunch of pineapples and misc. on two perimeter benches.  If you like avocados a Reed is a must have.  I have the best of the best some as individual trees, some as a cocktail tree - Reed, Oro Negro, Sir Prize, Holiday, Pinkerton, Ardith, Gwen.

Waldo (my wife is in that Reed tree somewhere).
(https://s26.postimg.cc/yyc2ugwid/Nancy_Reed.jpg) (https://postimg.cc/image/yyc2ugwid/)

Also, a VERY important consideration - you must provide for easy access for pollinators in the spring.  I have hundreds of different species of bees, wasps, moths, butterflies and flies pollinators every spring.  They get confused by any covering that restricts UV....can't find their way out.

BTW, your house is gorgeous.  Mine always looks like a train wreck, leaves all over the ground, but it works!
Title: Re: new greenhouse planning
Post by: Millet on September 23, 2017, 11:19:51 AM
Of course for citrus trees you don't need pollinators.  To cool my greenhouse during the summer months I use what is call a wet wall.  It works great in Colorado, a state with low humidity.  Keeps my greenhouse around 80-F even on the hottest day.  Cooling a greenhouse during the summer is much more difficult then heating the greenhouse in the winter.

http://www.greenhousemegastore.com/product/16600/greenhouse-cooling?gclid=CjwKCAjwjJjOBRBVEiwAfvnvBMB7KhBK29SavmphTviSq-7mFmHsUIhUiRgnern3Cq_YFkAAthN2PxoC5XUQAvD_BwE (http://www.greenhousemegastore.com/product/16600/greenhouse-cooling?gclid=CjwKCAjwjJjOBRBVEiwAfvnvBMB7KhBK29SavmphTviSq-7mFmHsUIhUiRgnern3Cq_YFkAAthN2PxoC5XUQAvD_BwE)
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 23, 2017, 05:22:23 PM
Of course for citrus trees you don't need pollinators.

You only grow citrus?

Last of the Lemon Zest mangos.   :-[ Wife made some awesome salsa out of this bad boy yesterday.  Served with tortilla chips, topped with Reed cado slices and it was a taste bud bomb!

(https://s26.postimg.cc/ir1nk1h1x/Lemon_Zest_Fruit_Sept22.jpg) (https://postimg.cc/image/ir1nk1h1x/)

(https://s26.postimg.cc/i5d6uuff9/Lemon_Zest_Fruit_Sept22_Salsa.jpg) (https://postimg.cc/image/i5d6uuff9/)

3 days of key limes yielded almost a quart!  Hands smelled of oil for hours and finger tips turned yellow.

(https://s26.postimg.cc/992eqwot1/Limejuice_2.jpg) (https://postimg.cc/image/992eqwot1/)

Title: Re: new greenhouse planning
Post by: Millet on September 23, 2017, 05:40:40 PM
Mark, I pretty much only grow citrus.  Other then that, I have one fully grown pomegranate tree, about 50+- pineapples and a  variety of tomatoes especially bred for greenhouse culture called Trust..
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 24, 2017, 09:42:30 AM
Mark, I pretty much only grow citrus.  Other then that, I have one fully grown pomegranate tree, about 50+- pineapples and a  variety of tomatoes especially bred for greenhouse culture called Trust..

Sounds good. I too got "greenhouse tomatoes" from Johnny's Seeds, one was Trust.  Found out regular hybrids do better like the BHN series or some oldies like Sunmaster which has the cold gene and sets in heat.  Incredible RICH taste.  Also found out I don't need to bother with caging.  My maters last year was from a volunteer that popped up near a mango pot, covered an area about 12' X 12', had the best maters from September until June of this year!

What pomegranate?  I have some Aggie research info on poms I can C/P to you.  They've studied them to death including public taste trials. 
Title: Re: new greenhouse planning
Post by: Tom on September 24, 2017, 10:49:36 AM
50 pineapples ! That's like the holy grail to me. How do your pineapples compare to fresh pineapple in Hawaii ? I got to go to Hawaii about 20 years ago and one of my best memories is how sweet the fresh pineapple tasted while we were there. I sent some to my closest friends by airmail, maybe over night (?). One of my friends is still talking about it. Unbelievable how much better fresh is ! I'm guessing your pineapple are better than anything you can buy in the grocery store at any time of year ? That's awesome Millet !!! Could you paste a link here if you have written about your experiences growing pineapples in your green house. Like do you grow them in your Rootmaker pots, how large, how long etc. ? Tom
Title: Re: new greenhouse planning
Post by: Millet on September 24, 2017, 01:20:18 PM
Tom I grow them in either 3 or 5 gallon RootMaker containers.  It really doesn't t seem to make much difference which size container I use.  I grow new plants from slips that grow from the sides of mature pineapple plants.  After breaking the slip from the mother plant, let it set on top of the bench for 3 or 5 days to develop some callas,  then stick it in the growing medium, where it will start to root.  In a year or so when the plant reaches approximately 3 feet wide it will develop a pineapple.  I let them remain on the plant until they turn yellow to insure a high sugar content.  The fruit sold in the supermarket are normally sold while still green.
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 24, 2017, 06:10:11 PM
Pineapples - here's a few of the comments made on my Facebook timeline to a friend on the subject today:

Tell ya what's crazy, for some strange reason all pineapples have grown a lot during the last month with one even pushing a flower. I just ordered some Dyna Gro Foliage Pro which is what I use to feed them in the cup. Might work great on pitaya too. Complete food, like 16 elements. Best food for foliar sprays too.

Got two White Jade, will save you a pup if I get a few. They've also come out of their runt stage and taken off. Also just got White Sugarloaf from Wellsprings Gardens. The store bought "twistees" are awesome if the plant is grown well. My last one was a bit stringy but it also came off a mediocre plant. I now label where my "twistees" come from - Hawaii, Costa Rica, etc. A good pineapple ranks up there with a good mango. Twistee:

(https://s26.postimg.cc/v0gmrehsl/Pineapples_July31_2.jpg) (https://postimg.cc/image/v0gmrehsl/)


That is one I harvested grown from a Kona store bought. Yes, you eat the fruit and then plant the crown.  Sugary sweet and rich if you let it go to a gold condition. The drill - 1. Twist (do not cut) the top off. 2. Let set overnight to callous up. 3. Starting at the bottom remove the lower 6 rows of leaves. The nodes showing are the roots. 4. Pot up in a 3 gal. pot of well drained soil, stake. 5. Fertilize via the cup with 1/2 tsp. of Dyna-Gro Foliage Pro often when active. Also, DO NOT water in the winter if they're in cold conditions like my greenhouse which gets down to 34F. It will induce root rot. Been there, done that. Watering indoors during winter near a sunny S. window is fine.

(https://s26.postimg.cc/69qydl2fp/Pineappletwist_2.jpg) (https://postimg.cc/image/69qydl2fp/)

Mark
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 24, 2017, 06:16:26 PM
Millet, I harvested the fruit of one plant recently, cut off the woody mother plant by sawing thru this 2" thick stem, left the pup alone and man is it going gang busters with dark green healthy foliage.  Needless to say it's benefiting from the established root system which you know has one helluva root system after 18 mos. in a pot.

I also scratch into the top 1" of soil a 18-4-9, 12 mo. encapsulated food with micros.

(https://s26.postimg.cc/z4mnh0k2d/Pineapples_July31.jpg) (https://postimg.cc/image/z4mnh0k2d/)
Title: Re: new greenhouse planning
Post by: brian on September 24, 2017, 11:00:20 PM
Mark, thanks for sharing details on your greenhouse.  You and Millet provide good examples of what can be successful.  I am thinking I will either plant directly into the dirt, or into bottomless root makers with a gritty mix like you describe.  Not sure yet, maybe some of both.

For cooling I am hoping that shade cloth and some kind of evaporative cooling will work.  I remember Millet had posted about his wetwall system and it was quite large.  I'm not sure how much I would need to be effective.  I'm looking at fogged systems also.  According to this chart: https://www.currentresults.com/Weather/US/annual-average-humidity-by-state.php (https://www.currentresults.com/Weather/US/annual-average-humidity-by-state.php) my area is around 54% afternoon humidity while Millet would see 35% in Colorado.  This means evaporative cooling will be less effective for me, but hopefully still worthwhile.

In any case I am keeping my trees in containers until I am confident that I can maintain proper temperatures.  In an emergency I can still haul them out.

For non-citrus, pollination is a concern.  However for citrus I've read that allowing free pollination can make for seedy fruit.  I need to have a plan for what I'll be growing to either let insects in or focus on self fertile fruit or artificial pollination.
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 25, 2017, 10:25:16 AM
For cooling I am hoping that shade cloth and some kind of evaporative cooling will work.  I remember Millet had posted about his wetwall system and it was quite large.  I'm not sure how much I would need to be effective.  I'm looking at fogged systems also.  According to this chart: [url]https://www.currentresults.com/Weather/US/annual-average-humidity-by-state.php[/url] ([url]https://www.currentresults.com/Weather/US/annual-average-humidity-by-state.php[/url]) my area is around 54% afternoon humidity while Millet would see 35% in Colorado.  This means evaporative cooling will be less effective for me, but hopefully still worthwhile.


I'm about to yank my Bonaire coolers out.  Getting real tired of the nasty pads, insufficient cooling, valves that stick.  Have been meaning to put in a high pressure fog system with rings around the fan outlets and perhaps some hanging from the rafters.  Here's a few links for you.
http://www.shop.truefog.com/product.sc;jsessionid=D787B4EDEE92508344D5A3E4C4B56793.p3plqscsfapp002?productId=63&categoryId=3 (http://www.shop.truefog.com/product.sc;jsessionid=D787B4EDEE92508344D5A3E4C4B56793.p3plqscsfapp002?productId=63&categoryId=3)
https://www.advancedmistingsystems.com/misting-pumps/ (https://www.advancedmistingsystems.com/misting-pumps/)
http://www.rapidcoolusa.com/installation.html (http://www.rapidcoolusa.com/installation.html)

My reservations has been my hard water, so, either I put in a very large collection tank for rainwater or water softener and then R/O system.

Note, metal gets hot as hell.  I should have painted the columns and purlins white before covering, did so after the fact.  I even blocked the sun by spraying the polycarb close to the metal.

(https://s26.postimg.cc/4h8px3nh1/Greenhouse_2.jpg) (https://postimg.cc/image/4h8px3nh1/)

I have 100's of pollinators, mainly bees, on the citrus.  Does not make the fruit anymore seedy.

They come and go thru the large vents.

(https://s26.postimg.cc/oihndsql1/Greenhouse.jpg) (https://postimg.cc/image/oihndsql1/)

BTW, what's the orientation of the long wall?
Title: Re: new greenhouse planning
Post by: brian on September 25, 2017, 11:08:25 AM
Thanks for the links!

I have very hard water also, and am thinking same thing.... rainwater or RO system.

I oriented my greenhouse to align with my house and driveway for appearance reasons.  Here's a diagram:
(https://i.imgur.com/GC5dGzI.png)
Title: Re: new greenhouse planning
Post by: Millet on September 25, 2017, 05:56:40 PM
A north/south orientation is the best for a greenhouse. Your is a little slanted, but should be just fine.
Title: Re: new greenhouse planning
Post by: forumfool on September 26, 2017, 08:13:33 AM
A north/south orientation is the best for a greenhouse. Your is a little slanted, but should be just fine.

Most recommendations I see are for east/west to have the longest amount of glazing facing south. This would be an advantage in the winter allowing maximum light but a disadvantage in the summer if you have trouble with a greenhouse overheating. Is this why you recommend north/south?
Title: Re: new greenhouse planning
Post by: Mark in Texas on September 26, 2017, 09:34:57 AM
A north/south orientation is the best for a greenhouse. Your is a little slanted, but should be just fine.

Ditto.  Oriented the rows of the vineyard also to run north/south.
Title: Re: new greenhouse planning
Post by: Millet on September 26, 2017, 12:18:03 PM
In east west orientated greenhouses the sun pulls the plants towards the south, because only the south side of the plants receive sun throughout the fall, winter and some of the spring.
Title: Re: new greenhouse planning
Post by: brian on October 13, 2017, 08:07:19 PM
Racing against the incoming winter.  The average first frost in my area is this week, but the forecast is good for the near future.  I can bring plants inside if there is a short cold spell. 

Starting to look like a greenhouse...
(https://i.imgur.com/ZjpA1jU.jpg)
Title: Re: new greenhouse planning
Post by: Millet on October 13, 2017, 08:56:45 PM
Brian,  your greenhouse looks just great.  Consider putting a couple ceiling fans in the top to push the hot air back down to the plant level during the winter months.  This reduces the temperature gradient between the inside top covering and the cold winter weather outside, therefore your heat lost to the outside air through to film is greatly reduced.  It helps keep the inside temperature warmer, and the temperature even throughout the greenhouse.  I have three 20-inch ceiling fans that blow throughout the day and night during the winter.   Spray a surfactant, Tween 20 is the common one to use on the inside walls to keep the greenhouse from dripping.  Great job -- congratulation on a job well done. 
Title: Re: new greenhouse planning
Post by: cory on October 13, 2017, 10:50:15 PM
It's looking really nice Brian.  Congratulations!
Cory
Title: Re: new greenhouse planning
Post by: Mark in Texas on October 14, 2017, 09:11:28 AM
My peak is 18' so a fan mounted high directed straight down helps.

Brian, what kind of covering did you use?

Looks great......

Another example of how important it is to get pollinators in/out.  Don't know why but my Gwen avocado's flowers were covered in flies last spring.  It worked, got fruit!

(https://s1.postimg.cc/9qc3dt33yj/Flieson_Gwen.jpg) (https://postimg.cc/image/9qc3dt33yj/)
Title: Re: new greenhouse planning
Post by: brian on October 14, 2017, 03:34:12 PM
Two very good ideas, Millet, thank you.   My kit comes with two circulator fans, but I agree a ceiling fan would be better for heat distribution.   I'd like to do both.   I have a lot of vertical space to work with so ceiling fans should fit just fine.   And surfactant on the walls is something I'd never thought of.

One thing I'm wondering about now is that the kit is configured so that the front vents and rear vent-fans are mounted about mid-height, which seems inefficient compared to a higher mount.   However, because the front vents are relatively huge (3ft across?)  there isn't much room to move them up before hitting the roofline.  The vent-fans are only ~2ft so I may be able to move them around, but could require moving the supporting frame a bit which will take time that I don't have right now.  How important is it that the fans/vents are placed high in the structure vs mid-level?

I'm still not sure what I'm going to do about pollination.   I'm leaning towards letting insects come and go, maybe just leaving front doors wide open in the daytime if they can't figure the vent slots out. 

One more thing... since I started building I'd completely forgotten that I originally intended to insulate the north wall.  However, beause the greenhouse is at a bit of an angle, the north wall  *might* be letting a significant amount of morning sun in during the summer months.  I doubt its that much, though.  Beacuse I dont have extra insulation on hand at the moment I am thinking I will leave it glazed for now and insulate it next winter if it doen't seem to provide meaningful light.

Mark, this kit comes with 6mm dual-layer polycarbonate.  I asked if they could do 8mm but was told it won't flex enough at the eaves.  It has been somewhat of a pain to install because if a panel isn't installed perfectly straight there is no way to adjust it - it doesn't flex sideways..  I had to shave an inch or two from the sides of some panels as I installed them to prevent overlap.  I am starting to see the attraction to polyethylene sheeting.
Title: Re: new greenhouse planning
Post by: Millet on October 14, 2017, 05:09:33 PM
Brian my front exhaust fans and rear intake vents are all at mid height.   For 10 years I called on the Colorado, New Mexico and California greenhouse industry when I worked for a large agricultural chemical company. All greenhouses have there exhaust fans and intake vents at mid height.  Never seen a greenhouse with them at ceiling height.  You don't want exhaust and vent high.  You want to retain the ceiling heat to use during during winter and use roof fans to blow the heat back down to your plants. In the northern hemisphere, the greenhouse north wall loses both heat and light.  The greenhouse would be much better off if you  insulated the north wall using those silver sided polyurethane insulation boards.  The silver coating reflects all the sun's rays back into the greenhouse.  The plants love it. The two most important greenhouse items are heat and light.
Title: Re: new greenhouse planning
Post by: brian on October 14, 2017, 07:30:44 PM
Thanks for the clarification on the venting.  Good to know I was worried about nothing - and don't have to waste time moving things. 

I hadn't considered that I was not only not receiving much light in the north face, but that it was letting light escape also.  Despite the 80% light transmission rating advertised on the glazing panels they cast a considerable shadow.   I have been thinking about painting the inside of the concrete foundation white, and looking into white pebbles to cover the floor.  The dirt floor makes it a bit darker than my old attic greenhouse that has the white floor and foil-faced walls.
Title: Re: new greenhouse planning
Post by: Millet on October 14, 2017, 10:02:35 PM
Another thought: If the exhaust fans and the inlet vents were located at the top of the two end walls, when the fans turn on all the incoming air would travel across the ceiling of your greenhouse and go right out the other end through the fans.  All that air that just passes through and out the upper level of the structure is the air that contains the CO2 that the plants need as their food source.  When the fan and vents are set lower, all the CO2 passes directly through and all around the plants.
Title: Re: new greenhouse planning
Post by: Mark in Texas on October 15, 2017, 10:53:28 AM
I'm still not sure what I'm going to do about pollination.   I'm leaning towards letting insects come and go, maybe just leaving front doors wide open in the daytime if they can't figure the vent slots out.

They get confused with UV inhibiting coverings.  Seems UV and a clear views of the sky is what drives them.

Quote
Mark, this kit comes with 6mm dual-layer polycarbonate.  I asked if they could do 8mm but was told it won't flex enough at the eaves.  It has been somewhat of a pain to install because if a panel isn't installed perfectly straight there is no way to adjust it - it doesn't flex sideways..  I had to shave an inch or two from the sides of some panels as I installed them to prevent overlap.  I am starting to see the attraction to polyethylene sheeting.

Glad you gotter done.  Polycarb is the only way to go.    Also, I think you'll be fine with the 6 mm.  I use a large Melnor propane heater mounted about 10' up but have a cheapie freestanding propane burner from Home Depot as a backup in case I lose electricity.  I also let my temps go down to 34F before the heater kicks on.  All the tropical trees flourish - rollinia, avocados, mangos, pineapples, surinam cherry, pitaya, citrus, etc.
Title: Re: new greenhouse planning
Post by: brian on October 16, 2017, 10:56:55 AM
Good to hear.  I have direct natural gas by pipeline at my house, and natural gas is dirt cheap compared to all other heating sources I've seen.  So, I'm not terribly concerned about heating but I hate to be wasteful.   I am planning to rent a FLIR (forward-looking infra-red) camera once the greenhouse is done to see how well the insulation is working and identify air leaks, both on the greenhouse and my home.
Title: Re: new greenhouse planning
Post by: Millet on October 16, 2017, 03:02:45 PM
I also have double wall 6-mm polycarbonate on my end walls and side walls, but went with double air inflated 6-mill poly for the roof.
Title: Re: new greenhouse planning
Post by: Mark in Texas on October 17, 2017, 10:19:16 AM
Good to hear.  I have direct natural gas by pipeline at my house, and natural gas is dirt cheap compared to all other heating sources I've seen.  So, I'm not terribly concerned about heating but I hate to be wasteful.   I am planning to rent a FLIR (forward-looking infra-red) camera once the greenhouse is done to see how well the insulation is working and identify air leaks, both on the greenhouse and my home.

Good plan.  You can buy a heat sensor gun for 13 bucks or so off Amazon.  Very accurate readings for anything from checking out hot/cold spots inside or outside of the house, barbequing, roasting coffee, etc.   https://www.amazon.com/HDE-Temperature-Infrared-Thermometer-Laser/dp/B00QYX6F5G/ref=sr_1_2?ie=UTF8&qid=1508249920&sr=8-2&keywords=heat+sensing+gun (https://www.amazon.com/HDE-Temperature-Infrared-Thermometer-Laser/dp/B00QYX6F5G/ref=sr_1_2?ie=UTF8&qid=1508249920&sr=8-2&keywords=heat+sensing+gun)
Title: Re: new greenhouse planning
Post by: Millet on November 03, 2017, 10:43:45 AM
Brian, it was a good decision to put in a deep concrete foundation.  When we built my greenhouse we only concreted each perlin in the ground, and insured that the polycarbonate sides went several inches under the soil .   Because of the cold outside temperature during the winter, and the warm climate inside, mice and other animals dig under the side wall to get inside.  Several times a winter I have to add a layer of dirt against the outside walls and reseal the animal's tunnels.   
Title: Re: new greenhouse planning
Post by: Mark in Texas on November 03, 2017, 02:44:40 PM
Brian, it was a good decision to put in a deep concrete foundation.  When we built my greenhouse we only concreted each perlin in the ground, and insured that the polycarbonate sides went several inches under the soil .   Because of the cold outside temperature during the winter, and the warm climate inside, mice and other animals dig under the side wall to get inside.  Several times a winter I have to add a layer of dirt against the outside walls and reseal the animal's tunnels.

You mean the columns, right?  I did the same thing and am having a bad rust problem at the base of the columns - Nexus Zephyr brand.   How about you Millet, any rust?  Mine started only a year or so after we built and I keep the floor dry.
Title: Re: new greenhouse planning
Post by: Millet on November 03, 2017, 08:54:52 PM
Mark, yes the columns. I also have a Nexus greenhouse.  I have not seen any rust, and the greenhouse was constructed about 20 years ago.
Title: Re: new greenhouse planning
Post by: brian on November 03, 2017, 09:43:06 PM
Yes I'm very happy with the way the foundation came out.   It was a ton of work but seems to have been worth it.  I expect the soil will stay warm.

I've had ~32F nights where I hauled all my trees into the garage, and it looks like a string of 28-30F nights is coming.  I have glazing up everywhere except the north side.  Once the north side is up it should hold some heat even though I will need to go back around and seal up various edge bits.  It is already 5-6F warmer all night inside the greenhouse than outside with no heating, despite the incomplete glazing.   I'm assuming this is from retained heat in the soil.

(https://i.imgur.com/9FiKgjO.jpg)
(https://i.imgur.com/OvDEmcF.jpg)
Title: Re: new greenhouse planning
Post by: Tom on November 03, 2017, 10:32:06 PM
That looks fantastic ! You have done a great job !
Title: Re: new greenhouse planning
Post by: cory on November 04, 2017, 10:01:34 AM
It really looks great Brian.  Soon you and your plants will be able to enjoy it. I look forward to hear and see how they grow in it.
Ciry
Title: Re: new greenhouse planning
Post by: Mark in Texas on November 04, 2017, 10:23:10 AM
Mark, yes the columns. I also have a Nexus greenhouse.  I have not seen any rust, and the greenhouse was constructed about 20 years ago.

That really pisses me off especially after complaining to the head sales rep and being told it was my fault.
Title: Re: new greenhouse planning
Post by: Millet on November 04, 2017, 11:13:59 AM
Brian your in the wrong profession.  You should have been in the greenhouse building business. 
Title: Re: new greenhouse planning
Post by: Susanne42 on November 05, 2017, 10:14:37 AM
That looks just awesome. Will be nice to see all trees inside :)
Title: Re: new greenhouse planning
Post by: Millet on November 05, 2017, 02:26:06 PM
Brian, are you planning on having a solid wall on the greenhouse's north end?  North walls of a greenhouse lose light to the outside.   A solid insulated north wall painted white on the inside does not allow the light to pass through as it would if it was glazing, but reflects the light back into the greenhouse giving more light and heat to the plants, (and the heat bill goes down).   Again great job.
Title: Re: new greenhouse planning
Post by: brian on November 05, 2017, 06:03:41 PM
(https://i.imgur.com/XEThgDa.jpg)
(https://i.imgur.com/SGPjDDl.jpg)[/list]
Title: Re: new greenhouse planning
Post by: Millet on November 05, 2017, 06:22:09 PM
 The exterior of the north wall on my greenhouse is glazing.  I put silver sided polyurethane insulation boards (4X8 2" thick) attached to the glazing on the inside north wall.  I guess it has been up maybe 15+ years with zero problems.  No mold, no nothing. However I live in a semi-arid area, but of course the humidity inside the GH is always high.  I also painted the silver insulation boards white, because white reflects sun light ever greater than silver.
Title: Re: new greenhouse planning
Post by: Badfish8696 on November 05, 2017, 08:54:04 PM
What about spray foam? I know they sell DIY kits. It does act as a vapor barrier so you wouldn't have to worry about moisture collecting behind it. The R value is very good per inch. It may be a challenge to get a finished look as you would probably have to cut some excess foam to get a smooth finish.
Title: Re: new greenhouse planning
Post by: BajaJohn on November 06, 2017, 06:37:07 AM
You can reduce moisture problems by using closed cell foams which are a natural vapor barrier.......
https://buildingscience.com/documents/reports/rr-0912-spray-polyurethane-foam-need-for-vapor-retarders-in-above-grade-walls/view
Many solid and spray/pour insulating foams are not closed cell and therefore allow diffusion of water vapor where it condenses on the cold side so be sure you use a foam that has vapor barrier properties. Apparently mealworms will eat polystyrene foam although it may not be their first choice in a greenhouse.
Title: Re: new greenhouse planning
Post by: brian on November 06, 2017, 12:36:41 PM
Millet, good to hear you aren't getting mold.  Am I correct in assuming you have a gap between the glazing and the foam board where the frame itself resides?  I worry that moisture would work into this gap and grow mold as there would be no airflow.  Given that you aren't seeing that problem, maybe my fear is overblown.  Perhaps the sunlight betweent the glazing and the foam is keeping mold from growing?  Or, perhaps you've sealed it so well that moisture simply isn't reaching that area.

BadFish and BajaJohn, spray foam is an interesting idea.  I use the canned foam to seal cracks, and it works well despite being an awful sticky mess.  It solves the problem of getting the insulation attached directly to the glazing/frame with little possibility for moisture penetration.  From reading that document you linked to it sounds like using PU foam without an extra vapor barrier is likely fine, as there is nothing that can rot in my greenhouse structure.  I'm not so concerned about it being perfectly flat... my biggest concern is that it's very permanent.  It would be nearly impossible to remove the foam from the frame if I ever need to disassemble any part of the wall frame.  I'm not sure why I would... but it worries me a bit. 
Title: Re: new greenhouse planning
Post by: Millet on November 06, 2017, 03:19:33 PM
brian, no there is no space between my insulation boards and the glazing.  The insulation boards are attached directly to the north wall glazing.  I sealed the instillation board seams with the silver sided tape.
Title: Re: new greenhouse planning
Post by: brian on November 06, 2017, 03:59:09 PM
brian, no there is no space between my insulation boards and the glazing.  The insulation boards are attached directly to the north wall glazing.  I sealed the instillation board seams with the silver sided tape.

How is this?  Doesn't the frame get in the way?  Or are your insulation boards fitted around the frame members?  For example, in the photo of my north wall, you can see metal framing that the glazing attaches to.   If I fitted the insulation flush with the glazing it would require cutting foam boards to exactly fit between the frame members.
Title: Re: new greenhouse planning
Post by: Millet on November 07, 2017, 12:20:52 AM
Yes, I cut the insulation boards to fit exactly in between the frames.  In fact I cut all boards 1/4" longer and wider than the frames, and squeezed them in for a very tight fit.  Being a polyurethane foam product they squeeze down nice and tight, plus I used glue..  Actually polyurethane boards are really very easy to cut.  I use a yard stick and a simple sharp kitchen knife. I did much the same for the back wall, which I put up each night during the winter, and remove each sunny  morning. Doing so greatly helps with the heat bill, which can be high in Colorado.
Title: Re: new greenhouse planning
Post by: brian on November 07, 2017, 09:21:59 AM
Ah, thanks for clarifying.  Yes, with boards flush against the glazing I wouldn't expect any mold to grow.   
Title: Re: new greenhouse planning
Post by: brian on December 06, 2017, 02:25:44 PM
...
Also, a VERY important consideration - you must provide for easy access for pollinators in the spring.  I have hundreds of different species of bees, wasps, moths, butterflies and flies pollinators every spring.  They get confused by any covering that restricts UV....can't find their way out.
...

So what is your solution to this problem?  Leave the doors wide open in spring?  That's pretty much my only option.  I have big double-doors so I would hope this is enough.  The glazing is UV coated of course so I'm not sure how to avoid the issue you describe.
Title: Re: new greenhouse planning
Post by: Millet on December 06, 2017, 03:13:56 PM
Many plants need polinators, but of course Citrus trees do not---neither does tomatoes nor pineapples as they are self polinating.
Title: Re: new greenhouse planning
Post by: Mark in Texas on December 08, 2017, 09:57:08 AM
So what is your solution to this problem?  Leave the doors wide open in spring?  That's pretty much my only option.  I have big double-doors so I would hope this is enough.  The glazing is UV coated of course so I'm not sure how to avoid the issue you describe.

The design.

I think you'll be OK.  If you have wide doors they'll find their way in and out.  Getting out is a bit tough as they use UV light to hone in on.  I assume they're attracted to flower aromas.

(https://s7.postimg.cc/jdblkp0t3/Greenhouse_South_Vent.jpg) (https://postimg.cc/image/jdblkp0t3/)
Title: Re: new greenhouse planning
Post by: Mark in Texas on December 08, 2017, 09:59:57 AM
Many plants need polinators, but of course Citrus trees do not---neither does tomatoes nor pineapples as they are self polinating.

You mean you're not in there vibrating your maters with a cordless toothbrush?   ;D

I have a lot of pineapples, some of the newer ones like the white boyz, others like store bought "twistees".  Just got a bottle of lab grade calcium carbide to play with this spring.  Got some White Jade getting up to 5' across.
Title: Re: new greenhouse planning
Post by: Millet on March 16, 2018, 10:08:55 PM
Brian, how about a new picture update of your new greenhouse?
Title: Re: new greenhouse planning
Post by: brian on March 18, 2018, 04:02:34 PM
The exterior still looks identical, but I guess I hadn't posted any pictures from inside yet!   In truth I haven't done much since the last update aside from add some bits of insulation that aren't really visible, and I've mostly levelled out the dirt inside.   I also painted the inside foundation walls white.

(https://i.imgur.com/jDhukLH.jpg?1)
(https://i.imgur.com/1a8UN1j.jpg)
(https://i.imgur.com/dBWdrPv.jpg)

dirt inside is now level, even though grade slopes around it
(https://i.imgur.com/8TJs0aq.png)

I still don't have proper heat or electric.  My HVAC contractor cancelled right before I left for a trip to India for a month.  I ended up putting all my trees in my basement the entire time, in darkness at around 50F temp.  However, they did just fine and I put them right back in the greenhouse when I came home.  I've been running propane space heaters when it gets below freezing, with circulating fans on an extension cord  :-\ 

It's just warming up enough now to get back on the utilities so I can finally be complete.   I have some ceiling-mounted circulator fans to install, also.  Then, the next thing to worry about is cooling.   I'm keeping all my trees in containers until I've made it through the peak of summer, just in case temperatures get out of hand.   

Last week I sprayed a surfactant on the inside walls of the polycarbonate glazing.  The product is supposed to eliminate condensation, but it did not work at all for me when I applied at the recommended rate.  The condensation came right back.  I am going to try doing it again with double the concentation before I give up and go with another product. 

Some of my trees had been struggling from the frequent near-freezing temperatures, and a handful that I severely under-watered had almost completely defoliated.   However, everything seems to be bouncing back.  Bare areas are all flushing like this:

(https://i.imgur.com/5zUOWCf.jpg)

Once the final heat and electric hookups are done I will looking into an automatic watering system, and likely some kind of active cooling such as a fogging system or swamp cooler.  I have public water and it doesn't seem to be hard like the well water at my old house.  I believe I can use foggers here without scale buildup. 

I have two sets of temperature sensors.  One is internet-connected and I can pull up the temperature from a phone app, and it can send text message alerts if temps get out of range.  The other is a simple radio sensor that runs entirely on batteries and has an audible alarm.  This way if I lose power, or if batteries die, I still have a backup alarm in case it gets too cold or my portable heater runs out of fuel. 

(the temp is really high on the sensors in direct sunlight, but the others show accurate air temps)
(https://i.imgur.com/0kdAOFr.jpg)
(https://i.imgur.com/8MdeIkV.png)

Because I'm running unvented propane heaters right now, and because I don't have enough heat to allow me to do much ventilation outside the warmest hours, I have a lot more humidity than I'd like.  I expect once I have the final utilities in place it will be more controllable. 

I haven't yet insulated the north wall.  I will probably save that for next winter.  I happend to find some cheap Ikea hanging containers (meant for some kitchen use) that work perfectly for hanging seedlings along the greenhouse structural rails.  I put all my trifoliate seedlings there, and beacuse they don't take up any floor space I am planning to grow many more for future grafting. 

Finally, I am thinking about putting white landscaping fabric down on the greenhouse floor to make it even brighter inside.  Right now my floor is just clay dirt which turns into mud when wet and so would the fabric brown.  However, I am thinking if I put a layer of much down first and put the white fabric on top the mulch won't stain the fabric and it should work pretty well if I sweep up fallen leaves occasionally.
Title: Re: new greenhouse planning
Post by: Millet on March 18, 2018, 04:26:42 PM
Brian, nice greenhouse.  When you have your main heater hooked up, you might not want it hoked directly into your electric source.  I have two 250,000 BTU over head heaters set to come on at different temperatures so that if one stops working the second one can take over until repairs are made.  When the greenhouse was built I told the electrilon to make one of the heaters with a two prong plug end,  that way if I lose power during a winter storm I can plug it directly into a generator.    Be sure to have the intake vents set up so that they open every time the exhaust fans turn on, and close when the fans shut off.  You did a magnificent job with your greenhouse, i really looks to notch.  I'm sending your tree on Monday March 19. 
Title: Re: new greenhouse planning
Post by: Tom on March 18, 2018, 05:15:33 PM
Brian, Everything looks fantastic ! Thanks for the update. Your dirty foot made me think of Adam Sandler in Mr. Deeds. Sandler had a black foot that had zero feeling and he played a prank on his butler. Also the butler was ridiculously quick and when asked about it he always replied ‘do not underestimate my sneaky ness ‘. There were other ongoing gags and I guess it’s my favorite Sandler movie ! Tom
Title: Re: new greenhouse planning
Post by: cory on March 18, 2018, 07:42:39 PM
Brian, your greenhouse looks great!  Thanks for providing the update.

Cory
Title: Re: new greenhouse planning
Post by: Mark in Texas on March 19, 2018, 07:48:13 AM
Yep, looks top notch!  Highly recommend a couple of these.  I went with non-vented for orchids, no fresh air intake provisional.  The thermostats are very accurate.   Worked great.

http://southernburner.com/ (http://southernburner.com/)
Title: Re: new greenhouse planning
Post by: Daintree on March 19, 2018, 09:43:12 AM
AWESOME greenhouse!  The size is fantastic!
Yeah, I love my Acu-Rite temp sensors, but have the same problem of trying to find a place in the greenhouse where the sun never hits it. Finally I just gave up.  After all these years, I know it never gets too HOT in there because the fan kicks on, and we don't have power outage problems.  My only worry is it getting too cold in winter. I have the low-temp alarm set, but not the high-temp.
Title: Re: new greenhouse planning
Post by: brian on March 21, 2018, 07:11:07 PM
Quote
..When the greenhouse was built I told the election to make one of the heaters with a two prong plug end,  that way if I lose power during a winter storm I can plug it directly into a generator.    Be sure to have the intake vents set up so that they open every time the exhaust fans turn on, and close when the fans shut off.  ..


This is a very good idea.  I was thinking I may be able to use a battery backup instead of a generator as I don't think too much electricity is needed to power the fans and heaters.  I'll have to do a cost comparison, I don't know much about backup power options.   As for the vents, I noticed that unless I pin them closed even a breeze will open them up, so I am reasonably confident that the suction from the large fans will open then, and if it does not I will find a powered solution. 

Quote
...Yeah, I love my Acu-Rite temp sensors, but have the same problem of trying to find a place in the greenhouse where the sun never hits it. Finally I just gave up...


I have enough sensors scattered around that I assume the coolest ones are correct when its sunny.  So if I see 85F/95F/100F its probably around 85F air temps.  I have a digital meat thermometer I use to check container temps to make sure the sun isn't overheating them and so far things have been ok.  I will rotate the white-painted side to point south as it gets warmer outside, and once they are in the ground it won't be a concern anymore.

Quote
Mark - [url]http://southernburner.com/[/url] ([url]http://southernburner.com/[/url])


I wish I had done more research before I purchased my heaters.  I would probably have gone with something different, but I will make do with these for now.  I see the Southern Burner heaters you linked to must be using an electrocouple thermocouple to ignite.  My gas water heater has the same setup, and I thought it was pretty neat that it doesn't require any power.  This would definitely be a better solution, but its too late for me to exchange my heaters.


Quote
Your dirty foot made me think of Adam Sandler in Mr. Deeds. Sandler had a black foot that had zero feeling and he played a prank on his butler. Also the butler was ridiculously quick and when asked about it he always replied ‘do not underestimate my sneaky ness ‘. There were other ongoing gags and I guess it’s my favorite Sandler movie ! Tom


 :D     I remember that one


Thanks for the kind words, all.
Title: Re: new greenhouse planning
Post by: Mark in Texas on March 22, 2018, 07:36:07 AM
Southern Heater has a thermocouple you hang anywhere for convenience.  Copper "cord" is probably about 5' long.  Been 20 years but remember it having a pilot flame that's always lit for ignition.
Title: Re: new greenhouse planning
Post by: brian on April 14, 2018, 04:20:14 PM
I now have electricity in my greenhouse.  Today is 83F with full sun.  My greenhouse temperature sensors are reading 93F when NOT in direct sunlight, and around 105F in direct sunlight (which doesn't mean much).  This is with vents open and exhaust fans running.  I believe I will need to implement some kind of cooling solution, and/or use shade cloth.  As an experiment I am going to spray a light coat of water all around to see how strong the evaporative effect is.  Weather report says it is 31% humidity outside
Title: Re: new greenhouse planning
Post by: Millet on April 14, 2018, 04:45:16 PM
Before I put a wet wall cooling system in my greenhouse, I used a shade cloth to help cool the greenhouse.  In fact iI tried several types of shade cloths, the one that worked the best is called Aluminet . You can find Aluminrt shade cloth on the Internet. Citrus grows best between 70 & 90-F.  At and above 95-F growth stops  and greatly slows down above 90-F.
Title: Re: new greenhouse planning
Post by: brian on April 14, 2018, 04:52:07 PM
Thanks Millet.  I am not sure which I will do first.  I think it depends how quickly I can get a fogging system set up before really hot days come.

After I sprayed a light coat of water around the greenhouse the temperature dropped 10F all around.  Not bad!
Title: Re: new greenhouse planning
Post by: Millet on April 14, 2018, 05:01:49 PM
I also used the water spray to lower the temps .Brian, check the GH temperature again in 15 minutes & you will find the temperature right back up. 
Title: Re: new greenhouse planning
Post by: brian on April 14, 2018, 06:04:03 PM
It stayed cool for a bit but the water hasn't evaporated fully.  I hope with a fogging system it could do a regular spray.
Title: Re: new greenhouse planning
Post by: brian on April 14, 2018, 10:55:29 PM
I looked a bit more into the battery versus generator power backup options.   From my brief research battery backups are pathetically inferior to generators.   I am somewhat surprised, given that batteries are powering cars these days.

"Most home batteries kick out between 3 to 9 kilowatts of power, and costs range from $4000 to $10,000, depending on the features you’re looking for in a home battery. "

Two 1/2hp exhaust fans use about 1.5kw/hr alone.   So the cheapest battery backup could only keep cooling fans running for... two hours?  For $4k?   

I liked the idea of avoiding the noise, size, maintenance of engines versus batteries but wow batteries really can't keep up for any reasonable cost.
Title: Re: new greenhouse planning
Post by: spaugh on April 14, 2018, 11:17:52 PM
You can get a few solar panels and a charge controller and a deep cycle battery to run everything offgrid for pretty cheap.  The beauty of solar for a GH is it will only need to work when its hot and sunny.  Anyways its way cheaper than the 4K you mentioned.  A generator is good too but will need to be manually started and setup unless youa are dropping big bucks on an automatic backup system.

Power went out at my house today for a few hours.  Had to run the generator to keep my GH fans and mist runinning.  It was 85 and 7% humidity outside and GH was over 105.

I have 50% aluminet and its still cooking inside the greenhouse unless the fans and mist are running.
Title: Re: new greenhouse planning
Post by: loneroc1 on June 15, 2018, 09:51:21 PM
Howdy all,

I've been watching Brian's project for a couple of years now. My 32 x 16 greenhouse with in-ground plantings is up and running, though I went for pressure treated and redwood construction, glazed with operable glass units for the walls and uv transmitting double walled acrylic for the roof.

I'm in zone 3/4 and when it's -20°F out two 30K btu heaters keep temps well above freezing. My goal is just to keep things just above freezing.  Here's my dilemma: I went with one Southern Burner ventless heater which needs no electricity to operate, not even a battery for the thermostat. (The other is a direct vent propane heater which requires an electric thermostat.)  When I bought the SB it was advertised as coming with a thermostat that would go down to 35F. Just above freezing so I was fine with that. I want the SB to be the primary heater. Well, when it arrived it came with a RoberstShaw millivolt thermostat that could only be set down to 39F.  When I called to inquire/complain I was told that RobertShaw thermostats now only go as low as 45F. and SB was aware of no other millivolt thermostat that had a lowered set temperature. I found another 39 F stat on ebay so I have a backup, sort of. I'd rather  not heat to 39, let alone 45. Is my SB furnace soon to be useless?  I like the reliability of needing no electricity.

The best suggestion SB could offer was to try to find an old millivolt thermostat wit a mercury switch and mount it on a slant.    My, what a helpful suggestion that was.  How can I operate the SB at near freezing temperatures? Or is my desire to heat without electrical back up doomed?

Any ideas? Thanks! Steve H SW WI USA USDA Zone 4.
Title: Re: new greenhouse planning
Post by: Mark in Texas on June 17, 2018, 08:11:53 AM
Howdy all,

I've been watching Brian's project for a couple of years now. My 32 x 16 greenhouse with in-ground plantings is up and running, though I went for pressure treated and redwood construction, glazed with operable glass units for the walls and uv transmitting double walled acrylic for the roof.

I'm in zone 3/4 and when it's -20°F out two 30K btu heaters keep temps well above freezing. My goal is just to keep things just above freezing.  Here's my dilemma: I went with one Southern Burner ventless heater which needs no electricity to operate, not even a battery for the thermostat. (The other is a direct vent propane heater which requires an electric thermostat.)  When I bought the SB it was advertised as coming with a thermostat that would go down to 35F. Just above freezing so I was fine with that. I want the SB to be the primary heater. Well, when it arrived it came with a RoberstShaw millivolt thermostat that could only be set down to 39F.  When I called to inquire/complain I was told that RobertShaw thermostats now only go as low as 45F. and SB was aware of no other millivolt thermostat that had a lowered set temperature. I found another 39 F stat on ebay so I have a backup, sort of. I'd rather  not heat to 39, let alone 45. Is my SB furnace soon to be useless?  I like the reliability of needing no electricity.

The best suggestion SB could offer was to try to find an old millivolt thermostat wit a mercury switch and mount it on a slant.    My, what a helpful suggestion that was.  How can I operate the SB at near freezing temperatures? Or is my desire to heat without electrical back up doomed?

Any ideas? Thanks! Steve H SW WI USA USDA Zone 4.

I heated a small greenhouse with a SB ventless too and yes the thermostat went down to around freezing.  That was around the 80's.  I'd consult an A/C Heating technician.  We have one here that's a wizard when it comes to such oddball units, work arounds.  I had a heater failure, temps dropped to 18F for a while, tech came out, knew the problem, did a work around in an hour.  Cheap $100 well spent.  Melnor propane unit.