Hi drgspc,

I agree, the panels will not stay in the Harbor Freight greenhouses in windy conditions if built as per the manual. Other methods are definitely needed in addition to using the spring clips. I'm glad you found your panels, and that your greenhouse frame wasn't damaged! Some folks don't get a second chance to make the structure more secure.

I have the 10x12 size, and we used screws with washers to secure the panels to the frame, as well as using extra clips that we ordered from HF. Other folks I know have used caulk in addition to the spring clips, but I prefer using screws as it makes it easy for me to change or remove the panels if I want to.

If it helps, here's a link to my blog about the 10x12:
Building our 10x12 Harbor Freight Greenhouse

And, here's a link to a good tutorial about building the 6x8:
Building and Improving the Harbor Freight 6x8 Greenhouse

Sounds like you are off to a good start, and I'm happy you were able to correct the problem. It's a clear shortcoming of the kit. We also found it helpful to reinforce our 10x12 with additional interior bracing to reduce flexing of the structure. We're enjoying our eighth year with ours.

I'd love to find out how this fix worked over the long run -- I have a polycarbonate greenhouse from a different company, but with the same issue. Thanks!

Hi bethiniowa,

Our Harbor Freight greenhouse has been up for over 11 years now, and I'm convinced the main reason is we put at least one screw through each polycarbonate panel, into the metal frame. It probably also helped that we added some interior bracing, because the HF10x12 framework isn't very beefy, and it's large enough so it can flex in the wind. As you can imagine a flexing framework can also cause panels to free up, but that might not be a problem with your structure.

I also added extra clips. The HF panels are held in place with spring wire clips along the edges of the panels. Even if your greenhouse isn't built that way, hopefully you can find a way to put a screw through the panel somewhere, into the metal framework.

Here's a link to Part Six of my blog, because it shows the kind of screws we used in our greenhouse: https://hfgh10x12.blogspot.com/2007/08/part-six-adding-panels.html

I accidentally tested my theory about the value of putting screws into each panel. A few years ago we had to replace the roof panels, due to sun deterioration of the HF panels. We forgot to put screws in one panel. Sure enough, within a month we had a bad wind, and that panel came loose. So, I'm convinced this is a good way to avoid that problem. Hope this helps.

Hi mudhouse, that's a very good idea, putting a screw through the panels, and the link to your well-written description is much appreciated -- Thanks! (Going outside right now to see how I can apply your suggestions....) -Beth

Glad to hear your greenhouse is still going strong. I'll definitely make those modifications to mine before winter. Thanks again!

OK, I've removed the plastic that I wrapped around my greenhouse and attached some 2x2 lumber that I had lying around, notching the wood over the aluminum frame, then screwed the panels to the wood. I really hope this will work over the winter -- we had a very windy day last week and several panels blew out again, and I'm lucky I was able to retrieve them from the yard. Thanks again for your suggestions, and crossing my fingers! -Beth

That looks great Beth! Using drgspc's idea of adding the wooding horizontals seems like a good solution to me.

Since you already know which panels you lost before, maybe keep an eye on those particular spots, to see if any of those panel edges are trying to move in a bad wind (I'm not sure how the panel edges are secured on your greenhouse.) I have one SW corner on my greenhouse that takes the worst brunt of the wind, and I learned over time that one spot needed a bit more reinforcing (an additional screw and more edge clips, in my case) to make sure nothing moved at all...even in really bad weather.

Good luck!

That's a really prudent suggestion, mudhouse -- I will definitely do that . I've already ordered another extra bag of clips and will put more in the panels that were always blowing out, and maybe a couple more screws with washers too. Thanks again! :-)

LOL well it's been four years, that's my pic at the top. Recently we had a freak windstorm over much of the country. We had winds 70- 80mph. I still have all the panels but barely. When the door blew off, the greenhouse inflated and the tops and bottoms of almost all the panes were out of the frames. Those little clips are almost worthless. the wood 1X2's were the only thing holding it together. I noticed that all the panels on the sunny (west) side are very deteriorated. I have been reading that replacing all the panels is not worth the $$$. Some suggest buying a whole new greenhouse.

If i gather the energy to start over, i may try to figure out a way to use nothing but wood 1X2's, top middle and bottom. Here's how it looked AFTER. Rocks in front of the door and tie=downs.

Oh one other cool thing. I tapped into one station on my sprinkler system that was not used, piped it into the green house and added drippers to all plants. Everything is still alive and i did not have to water by hand one time

I agree that it's completely unaffordable to replace a few panels -- I wonder why it's so much? One of my top panels broke apart (although the wood 1x2s held the rest in), and now I have a gaping hole in the ceiling. Maybe I don't really need a greenhouse....

The reason the panels are so expensive is the cost of double walled polycarbonite. It's not like regular plastic. They sell them at home depot and you can look them up and see just how much they cost. I imagine the supplier wouldn't be much cheaper because they have to make a profit too. The major cost of the entire greenhouse is those panels

I too feel like the bethiniowa...Maybe i don't really need a greenhouse. I have lost so many panels that I think my neighbors are building their own greenhouse for free with all of mine that have landed in their yard. I have scoured the internet for the same problem and found a solution that was different from the normal advice that has been given. I dont have a harbor freight greenhouse but a Halls and they all have the same problem. I installed 4 plastic dryer vents... 2 in the front and 2 in the back.. I cut the hole with a dremel and then installed them with 4... 10/32... 5/8 inch screws. The problem with these greenhouses is that air gets trapped inside and then has no where to go. The vents allow for the air to escape.

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I ended up getting rid of my greenhouse this spring -- it wouldn't stay together and replacement panels were so expensive that it was throwing good money after bad. And maybe if you live somewhere warmer than Iowa, a greenhouse makes sense, but here, greenhouse heating costs are so high that it's much cheaper to use florescent lights in an already heated space (my sunroom, in my case).

Here's what mine looked like at the end, top panels yellowed and broken out. My husband took it upon himself to put it (me) out of our misery:

Good luck with your greenhouse -- I certainly hope you have better luck with yours than I had with mine. -Beth

Thanks for documenting your journey! We've had a greenhouse for a 1 year now and the storm's blown off quite a few panels and clips. This honestly seems like a money pit with the wind tunnel we installed it in and the limited options on how we can address in our building. Considering to remove side panels and install a metal roof across the top which is really just going to be an awning at that point to use our backyard in. While they say the best thing to do is keep air out, I feel that's impossible so my theory is that opening up the sides will just allow the wind to pass through it instead of popping open like a balloon during the worst.