Quote Originally Posted by Simbilis View Post
Regarding insulation, http://www.fsec.ucf.edu/en/education...ingSystems.pdf says that conductive heat loss to the ground is extremely small compared to other losses. It's generally not worth the cost. However, you can get it if you want it - look for a dealer that sells insulated-wall pools like http://www.radiantpools.com.

I'm in northern VT, and I skipped the insulation. Can't tell you how good a choice that was, because we're still building
The document refers to Florida where the ground temperature is over 70 f and the air temperature average is 80 f. I've worked on some of this but with ponds and rubber liners. The losses are quite large. It also depends on soil and not just temperature but moisture content. Here in NE-PA we have clay which will retain moisture and is a good thermal conductor. Also they mention concrete as a good insulator and that could not be farther from the truth, it's more of a conductor than a iinsulator.

Think of the square footage of liner you have and the fact that the liner seperates the ground which is in my case 48 f and the water which is 80 f. If you just had r-5 or r-10 of insulation value you could save a lot in heating costs.

I also know from experience that PVC piping is a great heat exchanger with the ground. I've found a few easy ways to insulate the pipe and eliminate the problem. My favorite is to take say 2 inch pipe and wrap it with HVAC foil-bubble wrap while sliding it through a 3 inch PVC pipe. At either end I seal the pipes together with fernco (rubber) connections.

jongig