Good point about the warranties! Hmmm, my GH roof is almost always covered with an endless supply of desert dust. I can hose it off, but it will be covered again in no time (in spring, anyway.) I have had a lurking concern that IF there is a panel deterioration problem, it may be heat related. I read a post on another forum last year from a Tucson GH owner who'd purchased two 6x8 kits to use the poly panels in his own homebuilt wood-framed GH. He posted that after a few years the roof panels were brittle and breaking. I know he doesn't use his GH in the summer at all, and I figured his roof panels must have been subjected to extreme temps (if it's 110° outside, imagine what it may be inside an uncooled GH in Tucson, especially the air right under the roof panels...140°? 150°?) I hoped my plan to use the GH year round might help me to escape the same fate (I'm hoping I can keep the temps in mine under 100°, although most of my plants will tolerate that.) Still, I note that the three mentions of this problem so far (the Tucson person, yours, and Jamesy40's) have all happened in southern states. If heat is a problem, mine will likely fail sooner than some...so I'm keeping an eye on this trend! I guess it could be an opportunity to upgrade the roof to 6mm at least, eh? :-) Sheri

I lost 2 panels before I posted a fix earlier this site. I ended up buying a lexan panel at Lowes, that are thinner and way more costly than the original. Since it was only a temp fix and had to be done, I paid the price. After drilling 1/8" holes 1 foot from the bottom and top (on the vertical supports), I threaded a 12.5 gauge galvanized wire (TSC) thru the holes in a horizontal fashion. Curled the ends over at each corner. Repeated the procedure for the front, back and top sides. Used a single self tapping screw in the vent window. Winds since then have not bothered the HFGH. I checked the prices for replacement panels, and if you order nearly any quanity, the base price is high and then you have to add in extra shipping and possibly a crate charge, which makes the whole deal too much for each panel. Figuring everything all together, it is just cheaper to first secure the panels with the method I mentioned above. If you have lost a panel(s), then order another kit when they are on sale. My first HFGH was $299 + $20 Ship. The second one was $329 + $62 to ship. That is still cheaper than ordering any panels from anyone. Plus I have extra parts forever, to - add-on, repair, replace, etc. As far as a base for my unit. I used 2 ea 4x4's PT stacked. Used the PT wood to allow the base to be leveled, with 1 to 1.5 PT showing above ground. At the corners and mid-long side, I sank a 4x4 PT down 2 feet in the ground, anchored with 1 bag of concrete in each of the 6 holes. All the base is bolted together with carrage bolts. On top of the base plate, I screwed in a 2"x7'x1/4" Poly Trim that is used around garage overhead doors. Use a sealer between the poly trim and the PT wood to stop leaks. It won't rot. Then I used stainless steel screws (2"#10) every 6 inches to fix the alum base to the poly trim and PT 4x4's. Everything else is per HFGH Instructions. Then I topped it off with the reinforcement I mentioned above. In the center of this frame, I tamped Stone paver sand and rock base, topped with 24"x24"x2" colored concrete blocks. There is a 60W Solar Panel 15 feet away that runs the fan in the greenhouse to help keep it cooler. It helps.

I'm using Charlies clips and 1/4" diameter Fastenall aluminum bolts on mine. The clips from Charlies are significantly stiffer than those that come with the GH. The Fastenall bolts fit the channels in the wall and roof studs just fine. I was going to reinforce the corner wall studs as described by gardenerwantabe but found that once the roof studs were on the GH frame was solid. An experiment with a Univent automatic vent opener has convinced me these will be fine for this GH. I'll be ordering one for each vent. Hope this is helpful, SH

Hi oldlady59, our 10x12 has been up 8 years now, in a windy climate, using the screws and extra clips method. I didn't want to use caulk to secure the panels, because I like the flexibility of being able to remove them (the south wall of mine is replaced by screens in the summer time.) But I've heard good reports about using the caulk method, too. I don't know how hard it is to remove caulked panels, years later. People seem to report different experiences with the panels; my only guess is, it's based on climate and how severe the sun exposure is. Maybe there's even some variability in the manufacturing of the panels? I dunno. We had to replace our roof panels after a bit over three years. They were under Aluminet shade cloth, but our very intense sun in southern NM took a toll, and they were yellowed and full of small holes in the outer layer. Most of my side wall panels are now in the same state, but it took those almost 8 years. The panels on the north side of my greenhouse (sheltered by our house and interior insulation) still look like new. At the end of this thread, there's a discussion about a clear product that may be helpful in extending the life of the HF poly panels. I've used it and so has another GardenWeb member. So far it does seem to help, although I can't say for how long (time will tell I guess.) Harbor Freight Greenhouse polycarbonate panels failing When I order new side panels, I'll be using this product on them before installation.