Hi

I am considering a site which has a high water table which precludes a basement.
With slab-on-grade what are my options for insulating the perimeter? I would like to avoid exterior foam board on the slab edge and foundation stem walls (I don't like the looks of it and don't want bugs tunneling through it to get to the wood).

I could place 2" XPS vertically against the inside of the foundation stem wall before the slab is poured effectively insulating the slab from the exposed foundation.

However this leaves a piece of the flooring somewhat unsupported over the XPS.

It also leaves the base of the stud wall uninsulated at the corner where it meets the floor (kind of a downward diagonal short cut through the baseboard to the foundation stem wall to the exterior).

Anyway I am looking for advice on how to insulate this style of radiant slab. If you have a detail or sketch so I could visualize it that would be great.

Thanks

John

John Where are you?  Heating degree days?  
XPS has good compresive strenght and pouring concrete over it does not pose problems.  I would assume you have 2-4" XPS under the whole slab if you are using radiant heat?

There are a number of termite shields that can be the barrier between the foam and wood.  S simple metal cap can be used.

Eric