Asphaltic hardboard, extruded polystyrene, HDPE sheets and drainage composites protect membranes from rock-filled backfill, tamping, overburden placement and other trades. Protection goes on as soon as the membrane passes inspection and any flood test. Skipping it is a leading cause of punctures discovered only after a garage ceiling starts dripping.
Membrane's inspected, get the protection board on before the rebar guys start dragging chairs across it.
Also heard as
- protection course
- prot board
Related terms
Drainage composite
A dimpled or ribbed plastic core with filter fabric that carries water down to drains instead of letting it sit on the membrane.
Hot rubberized asphalt
A rubber-modified asphalt melted in a kettle and squeegeed onto decks as a thick membrane with no seams.
Plaza deck
A waterproofed structural slab over occupied space, topped with pavers, soil, planters or a wearing slab.
Flood test
Damming a membrane area and filling it with water for a day or more to prove it does not leak.