Fri, 7 November 2014
Engineer and permie Rob Avis from Verge Permaculture talks about building and designing passive solar greenhouses. Key Takeaways: Orientation. In Northern hemisphere orient it South or within 45 degrees of South. Higher the glazing transmisivity is, the better it is for the plants. Don't underestimate the value of good insulation in the walls of the greenhouse. Rob uses R-20 in Calgary. Keep in mind insulation doesn't stop heat loss, it just slows it down. In lower light conditions look to plants that are adapted to growing in lower light conditions. A hoop house may be a viable alternative in lower light conditions. It is very important to have thermal mass in the greenhouse. Thermal mass absorbs the surplus heat during the date and radiates it back out at night. Know what your goals are for the greenhouse. Why are you building it? You can't over-vent a greenhouse. Thermal curtains can cut heat loss drastically through the glazing. Show Notes: www.permaculturevoices.com/88 |