Here is my six-weeks update on my experimental, off-label use of Solar Blanket material sold as a pool cover/water heating and heat retention.
So far my results appear to be all that I had hoped for. Both of my greenhouses heat up better (when the sun is out) but since our late fall/winter temperatures are cool or cold, the heat-up is never excessive. They appear to stay warmer without the heaters constantly coming on, so that should pay off in electrical bills in the long run. You will notice that I used two different materials, one clear/translucent and the other silvery and translucent. You really can't see anything in my greenhouses at all through the silvery material and can only make out vague images though the clear/translucent material. Both "bubble wrap" materials are a thick 16 mil and are UV stabilized. There is an 8 year warrantee on both, but since I am definitely using it off-label, I am not sure that does me any good. LOL. The silvery blanket has an aluminized inner surface that is supposed to transfer heat better but for a 20x40' roll, it cost about $100 more.
I thought I would have to remove this insulation during the spring/summer months, but perhaps I won't. The aluminized surface might just end up being a great "shade cloth" and since I have multiple fans in each greenhouse, heat build-up may not even be an issue.
The lean-to is a Solexx greenhouse with PVC framing and the free-standing one is fabricated with typical double-walled polycarbonate paneling on galvanized metal framing. I put a roll-up flap over the double sliding doors of the free-standing greenhouse since these doors open out NNW and that's where our cold winds always come from. The doors have the insulation too, I just thought that a double layering would be effective.
