Understanding the pros and cons of using closed-cell spray foam to insulate beneath a concrete slab will help inform your insulation plan.
Insulating A Cathedral Ceiling With Foam Board - Building Advisor
Closed-Cell Spray Foam for Sub-Slab Insulation - GreenBuildingAdvisor
Spray Foam Insulation: Open and Closed Cell - GreenBuildingAdvisor
Insulating a Wood-Framed Floor Assembly - Fine Homebuilding
Below-Grade Under Slab system with FOAMULAR® rigid board insulation. - Owens Corning® Enclosure Solutions
Construction Design-Closed Cell Spray Foam Below a Slab - Northern Built
Insulate Carolina - Spray Foam for the Lowcountry
EPA Raises Health Concerns with Spray Foam Insulation
closed cell spray foam Archives - Hansen Buildings
Massachusetts Spray Foam Insulation