In zone 7b south New Jersey I have a 10×20 hoop house in progress. I plan to insulate the bottom 2 feet with R19 and the north wall with reflective foam core. The south wall will get UV rated bubble wrap. The north wall will get (10) 55gallon black barrels filled with water to be used for thermal mass. (It would be better to fill with sand I am told, but that is too much effort right now). The floor is concrete pavers.
Questions
1. How much antifreeze will I need to put in the barrels to prevent freezing?
2. Do I need to separate the barrels from the ground to keep the ground from stealing heat? I was thinking pallets and pink insulation as a cheap solution.
by Tronracer