On Wed, 16 Feb 2005 13:13:08 GMT, SteveF wrote:

How much insulation did you put under the slab and where? I was talking to
a radiant flooring guy last night in Washington who told me that WA now
requires 2" under the full slab.

That's what I used, in 1" sheets with seams staggered.

And what kind did you use?

R-5 styrofoam blue board. Ten years ago, not so many options. I
have the fiberglass reinforcement _and_ steel 6" mesh in the floor, so
any point loads _should_ be handled long before they get to the foam.

Dave Hinz