Retrofit: How do we tie-in existing footers and sill plate to an insulated plywood slab on grade? – GreenBuildingAdvisor

We hope to put a concrete-free floating ply floor in our slightly below grade walkout basement. Our contractors are not experienced with this floor, and we would like to provide clear simple information on the wall/floor interface. 

Contractor is especially concerned about:

1. how to bolt or screw down to secure exterior walls to footings without compromising the insulation and vapor barrier and 

2. How to secure interior wall framing to floors with only 1.5” of ply 

3. how to level sill plates where we have rough old strip footers.

Are these concerns solvable? Wr’d be grateful for any advice, articles, or diagrams for a retrofit situation.