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

https://online-wiki.win/index.php/Humidity_Control_in_Commercial_Buildings:_Impacts_on_Materials_and_Indoor_Air_Quality

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