Question on heating a greenhouse

  • Some of the links on this forum allow SMF, at no cost to you, to earn a small commission when you click through and make a purchase. Let me know if you have any questions about this.
SMF is reader-supported. When you buy through links on our site, we may earn an affiliate commission.

custom99

Meat Mopper
Original poster
Jun 21, 2011
294
13
Pittsburgh - South Hills
I have a 12 x 12 block building that I am thinking about turning into a greenhouse. One side will be windows. The front is all glass. this room housed a hot tub for 14 years but is not used anymore. I am planning on removing the roof and replacing it with clear corrugated roofing material. I live in Pittsburgh so my biggest concern is heat over the winter. Does anyone have any suggestions for me about the best way to go about heating it? I was thinking about looking on craigslist for an old small furnace. I am figuring I need to keep it in the 70 degree range since we are really big into tropical plants. Planning on tropicals, vegetables, perennials, and annuals. Any help or suggestions will be appreciated.
 
Custom99, morning.....  My buddy had greenhouses for his commercial operation, (cold country)..... I would suggest attaching 2" of blue foam to the walls... Second, in the winter, he suspended clear 6 mil plastic below the glass roof.... It provided a dead air space that reduced his heating bill by 50%.....  If you want even heat, put PEX tubing in the floor and heat using an electric hot water tank adjusted to 70-80 deg....

Seems like overkill but growing veggies year around at todays prices, it should be a wash or even a money saver....  I hate buying bell peppers and tomatoes at $2 each in the winter, and I usually don't..... Sell a few to your neighbors....  Check out pineywoods greenhouse system.... It is AWESOME.....   Dave
 
Custom99, morning.....  My buddy had greenhouses for his commercial operation, (cold country)..... I would suggest attaching 2" of blue foam to the walls... Second, in the winter, he suspended clear 6 mil plastic below the glass roof.... It provided a dead air space that reduced his heating bill by 50%.....  If you want even heat, put PEX tubing in the floor and heat using an electric hot water tank adjusted to 70-80 deg....

Seems like overkill but growing veggies year around at todays prices, it should be a wash or even a money saver....  I hate buying bell peppers and tomatoes at $2 each in the winter, and I usually don't..... Sell a few to your neighbors....  Check out pineywoods greenhouse system.... It is AWESOME.....   Dave
I was not sure if insulation on the walls would help since i was planning on just using the plastic roof but the 6 mil plastic sounds like a good idea since the ceiling height is going to be about 11 foot. We end up having our house look like a jungle in the winter from all the plants need to bring in. I love palms and they just take up so much space in the house.
What kind of floor does this building have ? 

Also keep in mind your going to need some sort of fan to exhaust when it gets too hot in the summer time ...
 
The floor is concrete. I was thinking about an attic type fan on a thermostat. 
 
How about an automatic vent?  I know they make gadgets that look like a door closer that open when too hot and then close when it cools.

Definately think about insulating the walls, and a water circulating system would be a great idea.  We had a greenhouse for years and up in Pittsburgh it would be a huge help.

Good luck, I want to keep watching on this one.
 
I'm a commercial greenhouse grower in northern Wisconsin and the advice of double layered roofing is solid but you need to keep air moving between the layers. Our houses are double 7 mil. poly with a inflater fan to blow up the air space between the layers. You should check into bio therm heating for your benching as this keeps soil temperatures up while air temps are not as high...better for maintaining healthy plants. Many people with a space as small as yours can heat the water for the bio therm tubing with a small hot water heater and a circulating pump. You have to vent the house at least once a day to exchange the air and air movement is important...aka small fan to keep air moving. There are many thermostatically controlled vents to chose from and it will come in handy on sunny days during the winter. I'm sure there is many things I'm forgetting but if you need help just ask...Len
Beer.gif
 
I did some research on the bio therm heat and will probably go with that set up for the tables. As far as heating the space, I found a site with a monthly heating cost calculator. I will be sticking with natural gas. Average cost for heating this space with electric comes out to $215 a month. Using gas heat it works out to about $42 a month. I am also planing on using black barrels as a passive heat to help with the heating cost. Does this sound like i am going in the right direction with this plan?
 
Sounds like a good plan. Also consider some top vents for the roof for summer cooling as well as the fans they would make a huge difference in the summer
 
SmokingMeatForums.com is reader supported and as an Amazon Associate, we may earn commissions from qualifying purchases.

Latest posts

Hot Threads

Clicky