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What is the gold test for damp walls?

Answer:

Using duct tape - securely tape all four sides of a piece of plastic wrap or polythelene film to the wall for 24 hours (or longer) period. Upon removal - if there is any moisture on the wall-side of the plastic - there is moisture infiltrating through the tested wall.

First answer by Bob811. Last edit by Bob811. Contributor trust: 1148 [recommend contributor recommended]. Question popularity: 2 [recommend question].