Time out for farm work: a passive solar greenhouse
September 2nd, 2009It’s been an unusually long time since my last post. But I’ve been busy at work on a passive solar greenhouse. The basic structure is now up.
That’s double-pane glass on the south side (and one panel on the west), gleaned from the Lebanon Re-Store run by Habitat for Humanity. Total price for four 4 x 5 double-glazed windows and a 36″ glass door: $175.
Roof and walls will be well insulated (roof R-29, walls R-19). Building materials – lumber and metal roofing – are recycled, saved from earlier remodeling projects around the house. Except for the purchased pressure-treated, the lumber is full-dimension Douglas fir harvested from the property and milled at the old Gaines Mill on Fish Hatchery Road, just a few miles away. Water-filled barrels will provide thermal mass. The biggest expenses were for insulation, a few pieces of metal trim for the roof, and screws and nails, which came to a bit over $300. The gravel for the pad was extra from the road-building project (to the left in the photo, going out to the barn).
We intend to use the greenhouse beginning in late winter as a place to start seeds and grow seedlings for transplanting into the garden, and then throughout the growing season for starting crops such as lettuces which need to be constantly replanted to maintain production. We’ve found that lettuces do great even in the midsummer heat, if they’re grown under a shade cloth.
That’s our apple orchard and sheep barn in the background.
The greenhouse is another piece of our personal program to become less reliant on an increasingly unstable economic system. I’ve been thinking about how to do it for years. Solving the thermal mass problem was the key to actually getting started. We’ve got four plastic barrels used to transport apple cider concentrate from South America that we got for free from Oregon Freeze Dry years ago, just sitting in the barn (they served as emergency fermentation tanks last year when we had a bumper grape crop). Why did it take so long to see the obvious?
September 3rd, 2009 at 9:23 am
Looks good! Great work, Jim. We look forward to seeing it in person when it’s all finished and working.