So we just started building our second glass house. If you search under my user name you can find pics of the first one. We moved even before we got to finish that one so the new owner got a great perk with the house :) Got the foundation and floor in this weekend (now have to run down and get the building permit!) and am waiting on Home Depot for 2 16 foot beams I need for the top sides. This one will be 12 x 16 with 10 foot high walls and and an 8 foot ceiling peak. The first greenhouse was 8 x 12 with 8 foot walls and a ceiling height dictated by the windows I had. This new one will have a metal roof so we will have a much steeper pitch. I went to pick up some windows from a lady on Craigslist and she also threw in these 2 great old french doors - really narrow and tall. They will be the focal point of the building. Can't wait to get the walls up. It's like putting a puzzle together. Someone on my facebook page said:" You know you can build a pvc hoop and plastic greenhouse for about $250." I said it wasn't really going to be used as a greenhouse and I wanted something a lot nicer looking than that for my glass garden house. It has to fit in with my 1780 colonial.

slchsu; Generally, greenhouse specific poly is guaranteed or has warranty for 3-5 years. This is usually the time that the manufacturer will guarantee the light transmission properties of their product. After this point the material tends to become more and more opaque, and depending on the quality, can become brittle, tear or just chunk off. the adage applies, you get what you pay for. When you are designing your greenhouse, design it such that replacing the poly in 5 years is not a huge chore.. i.e. you can use commercial poly holding clamps that just need to be undone, or fasten it in such a way that it's easy to remove.

Hi Sounds like a fantastic project. Afraid i can't help you much as our climates are so different Everything I have is vinyl,pressure treated or coated lol. Wood rots on the way home from the lumberyard in this climate lol I've used Thompsons water seal with some success. What do you intend to use for glazing and how will the framework be setup?? Usually requires very exact measurements to get the materials to fit together. Can't imagine it without dimensional materials Would like tio se it when you get it started gary

For what it's worth, I noticed you are zone 6, also. Eliot Coleman (from Maine) has some great books on Winter Harvest..maybe check the library. Notice it is "harvest" not "grow" in winter. I have had success sowing lettuce on March 1st and could harvest it by April under plastic when outside it was still freezing at night. It is amazing how warm it can get in there if the sun is shining, but you loose that heat overnight. My night time temps fall to below zero regularly over the winter and I still have edible leeks, green onions, garlic shoots, kale, carrots, parsley, and lettuce under plastic. My strawberry plant leaves are still green and alive, though not producing fruit right now. It's not so much the temps, but protection from the wind and elements I have found that make the difference. Also, selecting cold hardy lettuces and knowing when to plant them for winter use..similar to planning a fall garden. The trick is to pull the plastic really tight so the snow slides off. If it sags anywhere, then it spells trouble. My frame is made from PVC, using an up-cycled old deck as a "floor" on one section. This post was edited by pghgardengirl on Fri, Feb 15, 13 at 18:27