I’ve been dreaming of using our greenhouse for actual growing purposes ever since we stood out in the backyard and saw it for the first time. When we inspected it, I knew it would need a lot of work. The owners had left us a pair of rain barrels, one potting table, a selection of clay and plastic pots, and one empty greenhouse with a busted heating fan, questionable electrical system, and half-disconnected irrigation pump. Being a closet engineer, I’ve been dying to get to work on this, and Jen has been wanting to use it for growing stuff since last spring.

Since move-in day we’ve cleaned it up and found that the electrical system works fine—the flourescent lights need new bulbs and possibly new ballast—but the irrigation system made no sense. As far as I can tell, there’s a weird pump above the door which used to be hooked up to a water line which then pumped water between the two sheets of plastic which cover the greenhouse. It’s either that, or it vented something out into the air…but I can’t tell how or what.

Update: I think I finally figured it out. It’s an air pump, and it used to inflate the layer of air between the two sheets of plastic. Somehow, I guess, this increased the R value of the structure and kept things warmer.

The heater is still powered, but makes a frightening screech when it’s turned on. It sounds like a rusted or thrown bearing.

Last weekend I took a closer look at the outside of the structure and found out how the plastic is kept in place. It’s a simple tension system, where the plastic is fed into a channel on the frame, and a long strip of aluminum is then fitted into the channel over top, then gently tapped into place. They then sealed it with pounds of silicone caulk, which will have to be removed, but that’s a small matter.

Today, because we’re not getting hammered by income taxes, I took some of my IRS money and ordered a bunch of stuff: four lengths of UV-rated greenhouse plastic, a trio of 1 GPH misting nozzles and their respective PVC fittings, a hose-to-PVC connector, and a drain valve. My original idea was to use copper and PVC together, and drill small holes in a length of 1/2 PVC to mist, but I decided to spend an extra $15 to test out how the nozzles work. The rest of the PVC is off-the-shelf stuff, and should be another $20 or so. It should be here next week, and I’ll keep you up to date on the progress.