R405.2.2

Section R405.2.2 is titled 'Vapor retarder' and covers requirements for foundation drainage. For wood foundations, the requirement to provide a vapor barrier between the base layer and the slab of a basement is established. The purpose of this section is to prevent water from entering the building through the basement floor.

The model shows a section of a wood foundation and cutaway basement slab with a highlighted vapor retarder.