It gets hot enough here that the ability to allow a lot of air to flow through is very important to keep the heat down in a hoop house / greenhouse. When the hoop house was first built, I installed metal screen on the lower 3 feet of both sides. The idea was to later add some hoop house venting that would consist of a cover of plastic that could be rolled up or down depending on the weather. Up when it’s hot for some flow-through ventilation, down when it’s cold to keep the cold wind out (kind of). Well, for months the side vent covers were just rolled up and held with some spring clamps in the “up” position. It’s time now to get them working before all the stuff growing in the hoop house freezes to death this winter.
It was finally time to get the hoop house venting finished so the vents could actually be functional and not just a roll of plastic catching all the dirt and rain and junk that blew across the property. I really wish I had rolled them under so the weren’t so filthy when I finally decided to make the plastic roll up and down.
The Solution – Hoop House Venting
In order to get the vent cover to be able to roll up from one end, it was necessary to have something rigid that stretched the entire length (54 feet) of the hoop house. The vent cover would need to be attached to it, so it could be rolled up and down as needed. I decided to just use what I already had on hand, so made a long (55 feet) piece using 3/4″ rigid metal conduit and joining them with (approximately) 8″ sections of 1″ rigid metal conduit and 4 self tapping screws through each joint piece. It seemed kind of “floppy” to me, but I had read where other people made them out of plastic conduit with good results, so I thought metal should be at least as functional. (Joint shown below.)
I made clamps (shown just above) out of PVC by cutting a hunk out of a short section of PVC so the remaining piece snapped over the conduit when the plastic cover was wrapped around it. Well, it was sort of clever until I (literally) tripped over an old water hose in the garage and I thought to myself – “Why didn’t you just cut that up into sections, slit it down the side and pop it on the conduit for the same function?” – at about a tenth of the labor involved… Well, live and learn! (That’s the plan anyway…)
This is what it looks like when it’s all the way down. It gets so windy here that it will be necessary to add some method of keeping the thing from flying around and beating the screen (or me) to death. I think I’ll just use hooks spaced down the sides of the hoop house that somehow grab the metal piece to keep it in place.
I saw this idea on Pinterest and thought it was pure genius! The handle is made from iron pipe and the corners are also pipe fittings. Each handle has a 10 inch long 1/2 inch pipe, a 12 inch long 1/2 inch pipe, 2 1/2 inch pipe caps, a “T” fitting that is 1 inch by 1 inch by 3/4 inch. The 1/2 inch pipe fits nicely through the 1 inch by 1 inch portion of the “T” and the 1/2 inch part of the “T” fits onto the other 1/2 inch pipe. There is another elbow fitting that attached the handle to the metal conduit. It is a 1/2 inch by 1 inch fitting, where one end fits on an end of one of the 1/2 inch pipes and the other end was pounded (a little bit) onto the end of the metal conduit. This fitting is held on by a self tapping screw, although I did drill a hole in the actual fitting because I didn’t know how long it might take to “self drill” through the fitting. (If any of you know who the original poster was on Pinterest, please let me know and I will give them credit for the idea. I tried to find the photo again and couldn’t.)
The way the hoop house venting works (and it works very well) is the horizontal pipe can slide back and forth through the “T” fitting. That way, it’s possible to slide the pipe away from the hoop house and use it as a crank handle to crank the vent up and down. Once the vent is at the height needed, the pipe can then be moved back toward the hoop house and the vent stays at the height needed by way of the pipe preventing the handle from moving any further. I’ll get a quick video of how it works and post it here if there is any interest for it.
Just a note on the continuing story of the hoop house build. Rain gutters will be installed on the entire length of both sides just over the vent covers. Both sides will feed into a tote that is partially buried in the ground so it can fill completely via gravity. Out here in the desert, it’s necessary to catch every rain drop possible to use it the rest of the year.