We are building a new greenhouse, very small, mainly for conservation in the winter and seed-sprouting in the spring. But we don't know much about insulating in the winter. My spousal unit is making frames with plastic in them, to mount on the inside of the greenhouse. Does this make sense? I hear comments about bubblewrap but have no idea how it's used. My greenhouse is glass......
Very nice GH! Having internal frames that hold a plastic set inside your GH gives you a bit of insulation for your GH. Essentially, it'll be like a 'double glazing' window, with the added 'R' value of insulation.
Adding another layer of solar insulation with 'bubble wrap' will provide another bit of insulation, as well. The bubbled plastic serves to trap the warm air and release more slowly than a solid film of plastic. Glass in and of itself has very little 'R' value of measurable insulation. Any solar heat that has been contained in your closed-up GH will be easily lost as the outside temp decreases because there is little insulation. If you choose to heat your GH, the same heat-loss scenario will occur, so a more effective GH is one that can keep the heat in, hence the insulation layers.
We have a solar pool cover that was mounted on and over our GH. It is attached from side to side ( from the ground on one length up over the roof and down to the ground of the other side), like a tent that is pulled tightly to the GH. It emits all sunlight and provides no shade but does enable us to insulate the GH better than the PVC panels alone.
Along our north side, we have also added insulation panels. The reflective side is facing inward to capture the most sunlight possible from the daytime southern exposure.
I recently put greenhouse bubblewrap inside mine...I'll get a pic when I think of it :)
Grreaaaattt!
My husband lined my with bubble wrap earlier this fall. It's cut the propane usuage in half so far this winter.
Pam
woodspirit1 your greenhouse is looking great. Please post pictures when the frame is placed inside.
woodthrush is your greenhouse attached to your house?
No, it's free standing. It has a separate propane tank too.
Is propane cheaper than electricity for you? What is the normal winter temperature range for you?
I use the electric in the fall and mid to late spring, but the electric heater just cannot keep the greenhouse warm enough when the temps ready dip in mid winter. We're zone 4 here. Average daytime temps are around 30F for the winter months, January and Feb are the coldest months and we see temps anywhere from single digits to 20s for daytime highs. We've already seen -14 one night here this winter, but we usually get a lot more nights in January that will be that cold.
