1.   Damp at floor level will nearly always be due to plumbing and heating pipe leaks.

2.   Drain pipe leaks only drip when water is flowing out of the sink.

3.   If a supply pipe leaks or bursts, this is the valve to close to keep water from feeding into that pipe.

4.   The delay was caused in part by a steam pipe leak at U.N. headquarters.

5.   The pipes leak and the taps break.