Does anybody use hot water radiant floor heating?????

[Daintree]

Hi All,
I have a friend who is building a greenhouse next to his new pole barn, which will have hot water radiant floor heating.  For the greenhouse, the contractor said he could lay the pex tubing for radiant floor heat without pouring a concrete pad.  He would cover it with foamboard then bark.
Has anyone done this type of heating in their greenhouse??? Either geothermal or otherwise...
Thoughts???
Ideas???

Thanks!

Carolyn

[spaugh]

I would think the foam should go under the pex not above it. 

[SeaWalnut]

I am building radiant floor heating for my greenhouse but instead of water passing through pipes il use a burried chimney directly ,made from stainless steel and instead of plastic foam under the chimney,il use fireproof Ytong.

Something like this but with burried chimney and the fire hole will be actually outside the greenhouse and fed automatically with wood chips.
Its similar to the roman hypocaust sistem.
https://youtu.be/zul_Hdt667Y

[brian]

I thought about this.  Sounds like a good idea.  I sort of wish I had done hydronic heating instead of air.  PEX is really easy to use. 

The perimeter of my greenhouse is insulated 2-3ft down, so the soil stays reasonably warm in the winter.  My in-ground trees are growing so fast I'm not sure they need any additional encouragement, so I will probably hold off until I find something that struggles.