mudhouse - there was probably 10 inches of snow on the roof. I recognize that I should have gone out earlier and knocked it off but I'm a bit overwhelmed with life and business at the moment, and I simply didn't think about the risk of the weight on the roof. Actually, most of the snow we had received in the storm was very light and fluffy. The problem developed, I believe, after the storm broke and the snow began to accumulate moisture & weight as it started to melt. busy1 - I employed the same reinforcement of 3 lengths of EMD across the interior. That's nice for stiffening the walls but didn't make a difference in terms of this issue. ole_dawg - thanks for telling me about a guy on ebay. I'll have a look. If you happen to have the seller's name, I'd appreciate it. rosepedal - the 1x? material you have running from front to rear is sort of what I have in mind, but my thinking is that it needs to be centered between the ridge and the wall. Additionally, I would really want a minimum of one sturdy post, such as a 2x4, running vertically between those and the ground. This way there is some strength that prevents those boards themselves from bowing under the weight. As mudhouse mentions, the unsupported centers of the roof studs are the weak point. No question about it. Thanks for an occasional kick on this thread. It would be great if someone who has their remaining parts around might see this. I can be contacted directly at greg at greybearddesign dot com.

MissAgnes, I doubt that you will be able to locate specific statistics for snow or wind load for the HFGH (and I am very doubtful that Harbor Freight has this info, or will attempt to estimate it for you.) To be honest, their focus is not on long-term durability; it's on selling as many inexpensive kits as they can. The rest is up to us, as HFGH owners. I honestly have no idea how this might be calculated for the modified greenhouse; I can tell you that we estimate our modified greenhouse has handled wind gusts over 50mph on numerous occasions, and possibly a few 60mph gusts in the last six years, with no damage. However, our greenhouse is sheltered on the north side by our house, and we don't have any monitoring equipment, so this certainly isn't any kind of scientific evaluation. My guess is the wind resistance of the Harbor Freight greenhouse, built out of the kit, with no modifications, is ridiculously low (laughable.) In my opinion, it's almost certain to fail; it's just a matter of how much time before the event happens. There are many old posts here with sad tales of those who have watched their (unmodified) structure being permanently destroyed by wind. Also, many sad reviews on the Harbor Freight website, from folks who didn't know how critical the modifications were. Same story with snow load; I have no idea who would have exact figures, but I can tell you there are posts archived here of roof failures from snow. The weakest portion seems to be the center of the roof studs, so that's the area most folks focus on, when trying to build for snow load. I have gathered some links to older threads here regarding snow modifications, and they are posted in the Comments section of Part One of my blog (scroll down about 2/3 of the way through the comments at the page below, and look for the question posted by snwplwdrvr.) Part One, Building our 10x12 Harbor Freight Greenhouse Hope this helps!

Vicki, tell your hubby not to be such a nitpicker. The guy who levels the area can go a little bit over sized, and then it can be taken care of when you back fill to the size of the foundation. As far as the need for a true foundation, it looks like to me that this GH does not really require it. My recommendation is, unless you want to put it onto a poured concrete or laid concrete block foundation (which might require you to have a building permit) just dig holes at the corners, and about every two to three feet along the sides (on the inside) and set treated wood posts at least three feet deep. Then attach your treated two by eight base frame to it. I don't have one of these GH's yet, but hopefully someone who does will send you the dimensions from thiers. If not, open the box and find the instruction sheet. (If worse comes to worse, you may have to measure your base plates. I've bought Harbor Freight stuff in the past, and know first hand how "good" thier instructions are.) Kevin

svalli and kicksnj, I apologize to both of you for missing your posts. I haven't been able to check here for a while. My husband and I made our living by forging iron and fabricating items out of mild steel, so I'm pretty familiar with my old friend rust (we have a saying, rust never sleeps.) Steel is always trying to return to its natural oxidized state, but with modern finishes and a little maintenance, we can usually keep the enemy at bay (in most climates, anyway!) Sorry to hear that rust is trying to interrupt your greenhouse projects. Without seeing photos of the rusted bases, I'd tend to imagine the blistered paint and underlying rust are more of an annoying (and admittedly worrisome-looking) cosmetic issue than a true structural risk. My approach would be what kicksnj suggested; remove any loose or blistering paint with a steel bristle brush, rough sand paper, or rough abrasive pad. Then prime any roughed-up areas with a good metal spray primer (Rustoleum is good) and follow with another coat or two of a good spray paint made for exterior use (again, Rustoleum is a decent brand.) I'd sure rather pursue this approach than to abandon using the base, since as svalli mentioned, the clips that hold the vertical aluminum beams in place are anchored by the formed lip on the steel base, and then you have another set of challenges. I wonder if Harbor Freight has modified the finish on these steel bases, as our 4-year old base still doesn't show any signs of rust (but, we do live in a dry climate.) Svalli, since you've already constructed the two-by-four replacement base, I'm trying to visualize your challenge. I'm sure you've found that the hold-down connectors (part 47) do two things at the same time; they not only secure the aluminum floor plates (parts 1 - 6) to the steel base; they also attach the vertical aluminum wall studs, at the same time. So, even after you screw the aluminum floor plates to the top of your two-by-fours, you'll have to figure out how to attach the vertical wall studs to the aluminum floor plates, with no hold-down connectors to help. You may already have a solution for that, but I'm just making sure. The polycarbonate panels do touch the vertical lip of the aluminum floor plate; the panel clips (part 53) press the panels tightly against the aluminum frame, from the outside of the greenhouse, for air-tightness. It would probably be best if the screw heads did not fall in the area closest to the vertical lip, since it might affect the panel fit. The actual measurement from the outside of the poly panel to the outside of the aluminum floor plate can vary, depending on whether or not you use weather stripping between the polycarbonate panel and the aluminum frame. (I did.) What matters most is that you realize the poly panel needs to be able to fit tightly to the frame (or to the weatherstripping smooshed against the frame) if you want to avoid air leaks. If I'm misunderstanding, please feel free to post back! Again, apologies for my slow reply. I hope some of this helps. Hang in there, the challenge has been well worth the end results for me.