Author Topic: Policarbonate greenhouse recomendations  (Read 6265 times)

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #25 on: August 29, 2020, 03:35:40 PM »
I thought 4mm light transmission was very high, like 95%?  I am using 6mm which is less, and previously used 8mm which is like 80-85% with good results.  I think you'll be fine
thanks ,if you dont mind me asking ,why did you changed the 8mm with 6 mm poly ??

brian

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Re: Policarbonate greenhouse recomendations
« Reply #26 on: August 29, 2020, 07:26:15 PM »
My new greenhouse has bends on the sides, and 8mm doesn't bend much so they allow only 6mm which flexes more.  My old greenhouse had a single flat face for which 8mm was fine.  I would choose 8mm again if I could, it seems to be the best mix of cost, light transmission, and insulation value for our zone

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #27 on: August 29, 2020, 11:30:03 PM »
My new greenhouse has bends on the sides, and 8mm doesn't bend much so they allow only 6mm which flexes more.  My old greenhouse had a single flat face for which 8mm was fine.  I would choose 8mm again if I could, it seems to be the best mix of cost, light transmission, and insulation value for our zone
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Mark in Texas

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Re: Policarbonate greenhouse recomendations
« Reply #28 on: August 30, 2020, 08:39:20 AM »
I thought 4mm light transmission was very high, like 95%?

Not even close.  You won't even get that kind of LT with clear corrugated greenhouse grade. More like 88-90% with high grade clear.  Google is your friend.

If memory serves me correct when I was shopping coverings 4 mm double panel LT was like 60%.  Add as little as 5 years of age and dirt and fungi buildup (which is real and a PITA to clean) and your tropical faves which are home to full tropical sun will suffer.

Quote
I am using 6mm which is less, and previously used 8mm which is like 80-85% with good results.  I think you'll be fine

No way Brian.  Please show me some bonafide lab stats on that.

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #29 on: August 30, 2020, 10:57:33 AM »
I found this chart ,take a look..... now I am not saying it's 100% true , but seems reasonable . By your saying if 4 mm does let only 60 % light ,then 10 mm or up should  not let any, yet still they use them for growing plants. 

« Last Edit: August 30, 2020, 11:03:20 AM by Plantinyum »

Longranger

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Re: Policarbonate greenhouse recomendations
« Reply #30 on: August 30, 2020, 12:49:42 PM »
Expensive stuff but I am considering Solawrap for my greenhouse covering. Price aside it offers advantages over polycarbonate. Flexibility, similar or better durability, R value, light transmission and warranty. Also lighter in weight and does not have open spaces for mold and algae to accumulate. Also ideal for roll up sides if that is a summer consideration in your area.

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #31 on: August 30, 2020, 03:54:24 PM »
Expensive stuff but I am considering Solawrap for my greenhouse covering. Price aside it offers advantages over polycarbonate. Flexibility, similar or better durability, R value, light transmission and warranty. Also lighter in weight and does not have open spaces for mold and algae to accumulate. Also ideal for roll up sides if that is a summer consideration in your area.
I was actually considering of wrapping the greenhouse with this bubble wrap material in winter, to gain more heat in, but I am thinking and thats not from any experience ,that this I not a very sturdy material on its own .

Mark in Texas

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Re: Policarbonate greenhouse recomendations
« Reply #32 on: August 30, 2020, 05:52:13 PM »
I found this chart ,take a look..... now I am not saying it's 100% true , but seems reasonable . By your saying if 4 mm does let only 60 % light ,then 10 mm or up should  not let any, yet still they use them for growing plants. 


Like I said it's about memory when doing research 9 years ago.  I use a 10K footcandle meter and even with new clear Lexan brand corrugated clear I got about 6,000 f.c. noon, summer installed.  Ad bullshit is 90%.   Keep in mind these folks are out to make sales.  You also have to take into account structural members.

Palram SolarSoft 80 was not the 80% LT they claimed to be so I filed a warranty claim about 2 years into the installation.  They fought me tooth and nail. Had to clip a sample and send it to them for their "official" tests which I as a Joe Blow could not verify.  After a year of threats they actually gave in and replaced the entire roof, this time with my requested SolarSoft 90 which allows much more LT.

Buyer beware

Mark in Texas

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Re: Policarbonate greenhouse recomendations
« Reply #33 on: August 30, 2020, 05:55:06 PM »
Expensive stuff but I am considering Solawrap for my greenhouse covering. Price aside it offers advantages over polycarbonate. Flexibility, similar or better durability, R value, light transmission and warranty. Also lighter in weight and does not have open spaces for mold and algae to accumulate. Also ideal for roll up sides if that is a summer consideration in your area.

So they claim.  Let me know how things are going 5 years in.  I'm on my 8 year with this stuff and experience rules.

Mold and algae will grow inside and  out.

Longranger

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Re: Policarbonate greenhouse recomendations
« Reply #34 on: August 30, 2020, 07:09:58 PM »
Due diligence is far from complete. Will want to speak directly with several owners who have had this stuff in service 5 plus years.

brian

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Re: Policarbonate greenhouse recomendations
« Reply #35 on: August 30, 2020, 08:22:22 PM »
I thought 4mm light transmission was very high, like 95%?

Not even close.  You won't even get that kind of LT with clear corrugated greenhouse grade. More like 88-90% with high grade clear.  Google is your friend.

If memory serves me correct when I was shopping coverings 4 mm double panel LT was like 60%.  Add as little as 5 years of age and dirt and fungi buildup (which is real and a PITA to clean) and your tropical faves which are home to full tropical sun will suffer.

Quote
I am using 6mm which is less, and previously used 8mm which is like 80-85% with good results.  I think you'll be fine

No way Brian.  Please show me some bonafide lab stats on that.

You very well might be right on the percentages.  I can say though that both 8mm and 6mm twinwall have worked great for me for years. 

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #36 on: August 30, 2020, 11:30:51 PM »
Expensive stuff but I am considering Solawrap for my greenhouse covering. Price aside it offers advantages over polycarbonate. Flexibility, similar or better durability, R value, light transmission and warranty. Also lighter in weight and does not have open spaces for mold and algae to accumulate. Also ideal for roll up sides if that is a summer consideration in your area.
I was actually considering of wrapping the greenhouse with this bubble wrap material in winter, to gain more heat in, but I am thinking and thats not from any experience ,that this I not a very sturdy material on its own .

I'm going to line the sides with insultaion foil to reflect light and heat. I'm just an amateur so don't reccomend you mimick my ideas



haha, I might do your idea the next winter, cuz I havent build it yet  😀 till then I am waiting on reviews from you considering your idea . I
I found this chart ,take a look..... now I am not saying it's 100% true , but seems reasonable . By your saying if 4 mm does let only 60 % light ,then 10 mm or up should  not let any, yet still they use them for growing plants. 



Like I said it's about memory when doing research 9 years ago.  I use a 10K footcandle meter and even with new clear Lexan brand corrugated clear I got about 6,000 f.c. noon, summer installed.  Ad bullshit is 90%.   Keep in mind these folks are out to make sales.  You also have to take into account structural members.

Palram SolarSoft 80 was not the 80% LT they claimed to be so I filed a warranty claim about 2 years into the installation.  They fought me tooth and nail. Had to clip a sample and send it to them for their "official" tests which I as a Joe Blow could not verify.  After a year of threats they actually gave in and replaced the entire roof, this time with my requested SolarSoft 90 which allows much more LT.

Buyer beware
lolll everyone seems to be wanting to take the green stuff, the qualities of the product that they will sell you does not matter .
I thought 4mm light transmission was very high, like 95%?

Not even close.  You won't even get that kind of LT with clear corrugated greenhouse grade. More like 88-90% with high grade clear.  Google is your friend.

If memory serves me correct when I was shopping coverings 4 mm double panel LT was like 60%.  Add as little as 5 years of age and dirt and fungi buildup (which is real and a PITA to clean) and your tropical faves which are home to full tropical sun will suffer.

Quote
I am using 6mm which is less, and previously used 8mm which is like 80-85% with good results.  I think you'll be fine

No way Brian.  Please show me some bonafide lab stats on that.

You very well might be right on the percentages.  I can say though that both 8mm and 6mm twinwall have worked great for me for years. 
I dont have any experience with policarbonate, yesterday I was in one of the two ( of which i'm aware ) botanical gardens in Sofia , they are using polucarbotnate for theyr greenhouses. Dont know what the thickness was thought, looked to me like 6 or 8 mm. It is guite old ,was dirty and no more transparent ,yet the plants looked fine and did not look like they were starving for light. Its obvious thought that it stops light.
 

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #37 on: August 30, 2020, 11:48:47 PM »
This week I will be baying the greenhouse, I am still comparing the ones that I found for sale . Will post what I have choosed and ,def will be making updates of the building process.
I will be putting it on my tomato bed, which will no longer be such. Desided on the size of it to be 4m length , 3m wide and 3 m high. I only have to wait my tomatoes to all ripen ,so I can start doing  the ground insolation and build the frame for the gh. Mr

Mark in Texas

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Re: Policarbonate greenhouse recomendations
« Reply #38 on: September 01, 2020, 05:44:57 PM »
I thought 4mm light transmission was very high, like 95%?  I am using 6mm which is less, and previously used 8mm which is like 80-85% with good results.  I think you'll be fine

Get a footcandle meter that registers to 10K f.c.   You'll be lucky to read 65% or 6,500 f.c., summer day, high noon, clear skies

 If I remember I'll take some readings and post some pix indoors and out when conditions are good.   

« Last Edit: September 01, 2020, 05:47:24 PM by Mark in Texas »

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #39 on: September 02, 2020, 06:00:32 AM »
I ordered the greenhouse yesterday ,they will deliver it around middle of september, I will start the work around beginning of october when I pull the tomatoes from the place. It will be with a high of 2  meters since the particular producer said  they dont make them 3m high. I will be making a concrete and brick base, with which I will lift the greenhouse ,so it has more high to it . I will stop with the posting for now and will be back when the work begins !
« Last Edit: September 02, 2020, 06:03:15 AM by Plantinyum »

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #40 on: September 14, 2020, 02:45:26 PM »
Hello ,once again 🙋🙋😀 the greenhouse is here, still waiting on the tomatoes thought... I made a quick sketch of the base for the greenhouse / how I will be making it. Please take a look and tell me, is it okay that way. Anything I can add or discard ??
Note: right side is in, left -out.


« Last Edit: September 14, 2020, 02:48:01 PM by Plantinyum »

Mark in Texas

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Re: Policarbonate greenhouse recomendations
« Reply #41 on: September 16, 2020, 05:25:40 PM »
......,yet the plants looked fine and did not look like they were starving for light. Its obvious thought that it stops light.

And these fine looking plants were producing large crops of fruit?   ::)

Mark in Texas

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Re: Policarbonate greenhouse recomendations
« Reply #42 on: September 16, 2020, 05:33:54 PM »
Hello ,once again 🙋🙋😀 the greenhouse is here, still waiting on the tomatoes thought... I made a quick sketch of the base for the greenhouse / how I will be making it. Please take a look and tell me, is it okay that way. Anything I can add or discard ??
Note: right side is in, left -out.



I'm not sure what your goal is on the insulated footings.  Also suggests you may be over thinking this.  Flowering and fruiting trees/plants require high light for good production. Provide that and protection down to 1.6C and you'll be fine.

Also, I did footings for the columns and regret it.  It's much better to put down concrete footings and form up a beam, an outside bottom plate resting on them and then build your walls up on that perimeter plate.

brian

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Re: Policarbonate greenhouse recomendations
« Reply #43 on: September 16, 2020, 07:36:21 PM »
I don't believe that picture is showing a typical post footing, but rather the cross-section of a full perimeter wall.  The goal would be to insulate the dirt inside the greenhouse so it doesn't conduct heat out and to keep the soil warm enough allow in-ground planting.   If it were just a post/sonotube type footing then yeah it would be pointless to insulate it.

My suggested changes (pretty minor)
« Last Edit: September 16, 2020, 07:43:16 PM by brian »

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #44 on: September 17, 2020, 12:51:52 AM »
I don't believe that picture is showing a typical post footing, but rather the cross-section of a full perimeter wall.  The goal would be to insulate the dirt inside the greenhouse so it doesn't conduct heat out and to keep the soil warm enough allow in-ground planting.   If it were just a post/sonotube type footing then yeah it would be pointless to insulate it.

My suggested changes (pretty minor)

yeah its a cross section ,that just shows the idea better. Thanks for the details about the coating material and the sloping on the top, will def take them into account.
 I was wondering if the bricks are any good if they are under the ground level in the moisture. I mean I will cover them with a sand and cement solution and then will have the sturofoam on the outher side which will have also be covered with a net and teracol.
My direct guestion is ,is is good that way in a sence to not let moisture to the bricks ,which will degrade fast in a such environment ,or should I make a concreete base right up to the soil level and then work from there with the bricks ?? Thanks to anyone and have a nice day !🙋

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #45 on: September 17, 2020, 12:54:47 AM »
By the way, the work has started !!☺


brian

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Re: Policarbonate greenhouse recomendations
« Reply #46 on: September 17, 2020, 03:37:23 PM »
Looks nice!

Assume that anything below ground level will become completely saturated with water, there's really no avoiding it.  I would think bricks would be fine, but I never thought about it. 

Plantinyum

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Re: Policarbonate greenhouse recomendations
« Reply #47 on: September 18, 2020, 12:56:06 AM »
Yesterday I made half of the formwork and today will be putting the cement in . I made it to fix the level which had a light slope, and to make a more wide step on which to put the bricks later.






brian

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Re: Policarbonate greenhouse recomendations
« Reply #48 on: September 18, 2020, 03:18:03 PM »
looks great, nice work!

Mark in Texas

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Re: Policarbonate greenhouse recomendations
« Reply #49 on: September 19, 2020, 11:19:05 AM »
Nice job!