Moisture mapping: measuring a damp area

How it works

Depending on the material, readings are taken on the surface without damaging it, or with pins for wood and for readings below the surface. They are taken on a regular grid. The highest values are found closest to the source of the water.

When we use it

• at the start of every job, to define the affected area;
• to tell a leak apart from water ingress, condensation or rising damp;
• to document the damage in a water damage claim;
• to monitor drying after a repair, before the finishes are redone.

Limits

A moisture meter shows where the water is, but not for certain where it comes from: it guides the search, and other methods confirm it. Readings depend on the material, so they are compared with each other on the same surface rather than read as absolute values.