So I'm on this web site and looking at their diagrams for "massive storage". It looks to me like insulation, then a thick slab, then the main heated slab. Does that sound right? John heres the site. http://www.radiantsolar.com/solar_options.php

This system uses a layer of soil between the slab and the insulation as the storage system for the heat energy. I have not had the opportunity to use it on any our projects yet, but I definatly plan to. It is a simple system that would cost very little to add, and does not require large water storage tanks.

I have purchased from this company many times in the past 10 years and have always been inpressed. Their approach is to find simple ways to make things work well and they succeed.

Be sure to build your house with SIPs so that you can minimiize your energy needs to begin with and you will have great system.

Thanks for the reply.
I was thinking it was another cement slab. Dirt, hmm...... So the super hot solar heated water heats up the sub layer and then goes to a storage tank or directly to the upper (now only) slab?

John

Harv,

You might want to look at this web site:  WWW.ARTHAONLINE.COM  and check out the sand bed concept.