radiant greenhouses

doug_10

I have a customer looking to do radiant slab on grade for a greenhouse using plastic for the walls and ceiling. Anyone have any experience in this. Seems like a heavy heat load and strangely enough, my IPEX program doesn't have plastic as an option for walls and ceiling.

hr

Years ago

I installed a Crop King brand radiant greenhouse. I'm sure others have similar offerings. Mainly the function as root bed heating, as the plastic walls are very little insulation value.

To warm the space generally requires large unit heaters.


Rutgers University used to have a bunch of radiant greenhouse studies and info on their website. www.rutgers.com.

Another tip, pervious concrete is often used for greenhouse floors. A mix without the sand that allows irrigation water to soak through. Low psi, however, not good for vehicle traffic. Stay away from copper in a slab that allows water migration

hot rod

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

John Jr

Steve, I install a radiant system for a friend of mine in his green house 20 X 40. Double layer of plastic with air blowing in between the layers. What we did was laid Rfoil (from TVM) for insulation and poured a 4” concrete slab with 5/8 Wirsbo Pex tubing at 12” spacing. I almost went 6” but changed at the last second. Now I told him I didn’t know how good it would work and didn’t want to lose his friendship. I had a telydine boiler 100,000 btu/hr set up for propane that I told him I would give him just to get rid of it. So we installed the system and hooked up the boiler and set it up for outdoor reset. He filled the green house with his plants and couldn’t believe how good it worked out. Now I don’t know anything about plants but he trying to show me how good the root systems were coming along and all that. That was two years ago.
So he also built a 45 x 55 work garage at the same time and was ready to install radiant in it this year. So this summer he asked me about the Viessmann boilers that I use and I told him that it would be great for his building. He asked me if we could install one in the green house so I installed a Viessmann Vitoden 200 15-60 in the green house and removed the system that was in the green house and installed it in the garage.
About a mouth after it was running he called me and told me that his green house was running on less gas than his garage was and that the green house was heating even better than before.
I can’t figure that one out the green house is all heat loss and the garage will hold the heat. He has two tanks set up and gets tickets from both so he can see what his operational cost are on his plants.

John Jr.