I used 10' lengths from Home Depot. I didn't flatten the ends, I just bolted it in. At the corners near the rear wall I used 90 degree bends (sold at home depot) with EMT connectors. This gave me a solid U shaped reinforcement. For the overhead cross braces, I did flatten the ends and bolt them to the existing EMT. I used long 6mm bolts from Fastenal for all of the attachment. They slide into the grooves of the vertical T braces. A hacksaw goes through it really quick. You don't need any special cutter. Just get a blade for cutting metal.

Ray, Your pictures are great! My DH and I saw the 10 x 12 GH for sale in the HF magazine for the first time today, so I've been reading this thread and others with much enthusiasm. How do you feel about your HFGH now? I was feeling discouraged after reading other posts, but after seeing your detailed pictures and instructions feel that we can tackle this and be quite satisfied. Lisa

OK, I'm back. Eastpenna, ordering from Harbor Freight is sorta like herding cats through a three-ring circus. Always an adventure. ;-) The person you spoke with was incorrect and/or confused; the clips are still available. Here is the info you need to call back with. The clips are identical for both the 6x8 greenhouse and the 10x12 greenhouse. However, Harbor Freight uses different part and SKU numbers for each kit. I asked him to look up both for us, so I could post it all here. He said to be sure to give them the SKU number and that will avoid confusion. (Good luck with that, lol.) For the 6x8 greenhouse: Part number 46 panel clip SKU number 27339, set of 72 clips, $9.99 For the 10x12 greenhouse: Part number 53 panel clip SKU number 29457, set of 130 clips, $15.99 Hope this helps, feel free to post back if this doesn't work. Be prepared to speak slowly and be persistent. ;-) Sheri

I built this greehouse specificially for starting bedding plants. I don't start heating it until the first week in Feb. At the time I didn't think a ground heat sink would have that much effect so I didn't do it. If I had it to do over again I would put the lip of the 2x4 base to the inside and put some foam board into a trench and up to the redwood around the base on the outside. The insulation on the north side just goes to the bottom of the redwood. The trays didn't melt uniformly along the whole shelf. It was just the 2 trays or so in the corners on the top shelf where the light would get concentrated. None of the seeds in those trays germinated however. Low angle sun reflecting from the top combined with the corner reflection against the dark plastic of the trays made for some real hot spots. I you look at my weather station at http://wx.uvci.com I have a temp sensor in a tray of soil on the soil heating germination mat. When the soil is dry and a bright sunny day the temp will get up to 130 easily. Another change I would make is to have the potting bench in the end just sit on supports rather than build it in. That way it could be easily taken out when not in use. It would make getting to the last two feed of shelf much easier. It also gets a lot of water on it when watering which has caused the composit material it is made from to expand. I will probably replace it next year and when I do It will not be built in permanently like it is now.