flowable fill and frost heave

huangyhg

flowable fill and frost heave
i've got a swimming pool project where the bathhouse is a concrete masonry structure with wood trusses for the roof.  there is a maze of masonry walls within the bathhouse - partitions between toilets, small closets, etc.  
the architect has told me that the bathhouse may be unheated, and this is located in the midwest with cold winters where the concrete slab-on-grade would potentially heave with freezing of the subgrade.
has anyone used flowable fill (clsm) with a low cement content for this purpose?  i'm thinking that we would overexcavate the footprint of the building and then backfill with the flowable fill.  then the contractor could excavate through the flowable fill and construct the main building footings as flowable fill is diggable if the cement content is kept low.  the interior "maze" of walls could then be placed on the slab.
comments?