Michael Tiffe : Might I suggest the use of phase change drywall to gain more thermal mass

Corey Schmidt : Thanks Michael, for the suggestion! very interesting! i never heard of that before but will research it. the OSB was specified for cheap and easy, since you can just paint it, but it is about 7$/ sheet more here than normal 1/2" drywall.

Corey Schmidt : i did a bit of reading and can't find phase change drywall for sale anywhere, but it has been used at least in Los Angeles, one of the articles here http://www.thermalcore.info/field-test.htm is about a home in LA. product information says it requires a skim coat. In my design, the 1" concrete on the floor using local sand is a cheap source of thermal mass, but also time consuming. I will keep my ears open about this stuff, as I work as a carpenter.

Robert Hones : The basic unit may be built in a few days by anyone with carpentry knowledge and the right tools because there is little cutting required. | driveways hamilton nz