intended to stop water from getting through something and causing damage, for example in the walls of a house

On top of concrete, you will need a damp-proof membrane. 在混凝土上面需要加一层防潮膜。

I don't think the damp-proof treatment that you carried out has had any effect. 我觉得你做的防潮处理没有任何效果。

able to avoid being damaged by water getting through something

She wants to make the shed damp-proof and give it proper windows. 她想让棚子防潮，并适当地开些窗户。

These paints are not damp-proof.

to make changes to a building, for example to its walls, that are intended to stop water from getting through and causing damage

The thick walls are built from earth and there is no point in trying to damp-proof them. 这些厚墙是用泥土建的，不需要作防潮处理。

The house had to be rewired and the basement had to be damp-proofed. 房子必须重新布线，地下室必须作防潮处理。