Subgrade Slabs and Water Management: Drainage, Vapor Retarders, and Gravel Layers

https://research-wiki.win/index.php/Remedial_Waterproofing_Strategies_for_Existing_Facilities:_When,_Why,_and_How

Subgrade slabs sit at the interface between the ground and the building enclosure, and what happens there often determines how well a structure performs against water intrusion for decades