Purchasing Used Greenhouse Questions?

[Ray]

Actually, it looks like Boise weather is pretty similar to ours. We're a bit north of Philly, and run about 5°F cooler.

No doubt the fuel cost could make a difference. We get killed on propane. I did add a propane heater to a porch to make it a 4-season room, so that added to my consumption.

Looking at climate-zone.com, I see that your average minimum from Nov-Feb is about 25°F. On the assumption you want your greenhouse no lower than 50°, and the temperature will NEVER go below 25°, you're going to need about 25 BTU of heating output from a heater for every square foot of surface area of the greenhouse (a little more or less, depending upon the cover).

If that 20' x 30' GH was a quonset hut (hoop) style, it would have a total surface area of about 1300 square feet, so you'd need about 32,500 BTUs, meaning about a 40,000 BTU (input - that's how they are specified) heater. As I keep my GH at 65°, and I know that sometimes we see single digits, that same GH would need about double that.

Play around with this as you consider greenhouses: Heater Size Calculator

[Becca]

Thanks for the info Ray! This will really help me out! We usually see a couple weeks of single digits during the winter and a couple of weeks in the mid teens too. Hubby thinks building a sun room would be just as expensive as a nice green house. I was thinking a greenhouse properly set up with plumbing & heating (natural gas) would be around $10,000.00 easily. I think a sun room plumbed and heated for my orchids would be double that possibly!

[dounoharm]

well, it costs a bit to set up a gh....i had to put in a nice foundation too, but i think it has really helped to have it on a perfect level and properly laid with gravel....and i had to pay a lot to run my water as it was a far distance....i think 10K is a reasonable figure for a gh, tho i spent more on my 12x24 when all was said and done....so a glass room on your house would be very nice....i wished many times that my gh was attached to the house....