Hi everybody. I originally posted this message to mudhouse's blog, not knowing how to post it here. But, now I do! So, if anyone gets this message twice, lo siento mucho. Anyway, here it is: I have a question about possible corrosion on my new, unassembled HFGH 10x12. The gravel has arrived, the foundation timbers are in place, and I'm ready to build the greenhouse. But, before I begin, I wonder if someone can enlighten me on potential electrical contact corrosion where (mudhouse's) steel "L" brackets connect the EMT to the frame, where the hold-downs meet the steel base, and where the studs also meet the base. Should I somehow insulate these contact points, perhaps with rubber? Is there actually a problem at these spots? Thanks so much. masscactus - ready to build

I must admit that you guys seem like a happy group for people that admit that they bought a less than quality product but decided to make the best of it AND MAKE IT BETTER. That is why AMERICA will always win. We never quit. I personally grew up on an Island, connected to the mainland by a bridge, granted, but the nearest town of any size was 42 miles away and it wasn't all that big either. My father could make ANYTHING FIT or WORK and I can recall time and time again when he did just that. I am very pleased to acknowledge that I have those genes running in my veins. The Oreintials (read China) might be able to make it cheaper, but WE make it BETTER. I absolutely LOVE to read how y'll have improved and strengthen those little flimsy, twisty pieces of left over beer cans and made them into things of beauty and STRENGTH. Long live Reynolds Wrap and Alcoa as well. Give me another beer would you. In a bottle if you please 1eyedJack and the Dawg Stay tuned for the upcoming saga of "The Greenhouse from Hell"

Troy, we have a similar set up. I also have strong winds blowing on the doors. I have a fan on the back wall, and the fan louvers bang open on windy days with the GH doors open. We also only used one screw on our roof panels, in the center brace (and extra clips.) I agree, thank goodness for the EMT bracing recommended by Gardenerwantabe and others here. Im coming to two new conclusions. First, I think you're right about the unsecured bottom of the roof panels being a risk in some winds, based on your observations of the roof panel bottoms flapping up and down, and bwrights experience of losing screwed-down roof panels twice. (Thats the first post Ive seen about the loss of screwed-down panels.) I taped the bottom of our roof panels to the greenhouse frame, but only because we were one of the "lucky ones" whose roof panels were not quite long enough to project over the gutter as shown in the manual. Not everyone has this problem, but Laserfan used aluminum tape to bridge this gap on his HFGH, so I did too. I was not trying to prevent the wind from getting under the roof panel bottom, but thats probably been (accidentally) protecting our roof in high winds. This also fits with bwrights comments about using the Freezer King tape to similar advantage, to make sure all edges are sealed. Heres our roof panel at the bottom edge: Second, Im starting to see the roof vents as a fairly big risk for people in very windy areas. My kit may vary from others, but the poly panels in my roof vents were a bit too short to prevent movement in the vent frame. They fit tightly from side to side, but after each window was assembled, we could slide the poly panel up and down in the window frame, about 1/4". During one bad storm, I almost lost the poly panel from one of the roof vents. The wind had pushed the panel up in the frame so the bottom edge of the poly was exposed, and the wind got underneath and pried the panel part way out of the vent frame. I climbed up and taped it to get through the night. Next day, we removed all four window vents, and I caulked each poly panel in place on the outside of the window frame. The poly panels no longer wiggle in the vent frames. But, I still have the problem of bad winds lifting up the vent frames up (maybe ¾"?) even though the vent handle is locked in the last hole ("closed down") position. Wind picks up the vent frame, and when the gust stops, the vent doesn't always fall back in place correctly, so it's ready to be picked up by the next gust. If this happens over and over again in a storm, maybe its enough to shake the window stop out of the hole in the roof vent handle...? Once that happens, the whole vent frame could flip over backwards until it popped out of the roof peak channel (I watched that happen while building the GH, retrieving one vent window from our house roof.) If a roof vent fails, wind likely rushes in and puts pressure on the weakest points from inside the GH. If all the panel screws hold, the doors become the next weakest point, so they blow outward. Thats one theory, anyway, and right now Im thinking the safest thing is to leave my vents wired down permanently, since I cant figure out how to prevent the frames from lifting up that 3/4" inch (or so) in a high wind. Wish I had a better solution, but so far Im stumped. I'll add some of this info to my HFGH blog in case it helps others. Thanks for all the good posts here! Good luck with the door rebuilding Troy, looking forward to your pictures. Sheri

That is a nice link you posted there. I am sory but I do belive the webpage title greenhouse.gov actually means "green"-house as in energy efficent not Greenhouse for storing/growing plants. The only place I read where they say not to insulate the floor was if I was trying to cool the house. As I said earlier I am using this greenhouse for winter protection. The R values that they use in Austraila are measured differently then here. I can only imagin that R 1.5 would be close to the same as our R 13 for exterior walls and R 30 is normal for cielings here but they call it R 2. Below is from the Department of Energy link..... Insulation Priorities It is most important to: Insulate your attic to the recommended level, including the attic door, or hatch cover. Provide the recommended level of insulation under floors above unheated spaces, around walls in a heated basement or unventilated crawl space, and on the edges of slabs-on-grade. Use the recommended levels of insulation for exterior walls for new house construction. When remodeling or re-siding your house, consider using the levels recommended for new construction in your existing walls. Next Section - How Does Insulation Work for You? Here is a link that might be useful: Department of Energy