Bridging damp or ‘lateral penetrating damp’ is the term use to describe damp caused by high external floor levels or by building defects.
What is Bridging Damp?
Bridging damp is damp caused when the external ground level is higher than the built in damp proof course or the internal floor level has been built up above the damp proof course where the original floor has no damp proof membrane below. This means that the masonry will be wet at a relatively higher level and signs of damp will begin to show on the internal walls of the property. There can also be bridging damp from defects within a cavity wall were debris builds up at the base of the cavity to an extent were it has gone above the damp proof course and is then transferring the ground water up over the D.P.C and is now creating damp walls, this is usually at the base of the decorative wall and as with rising damp it can still contaminate plaster with ground salts.