Mold can start growing on surfaces with a relative humidity of 70 %RH. Measuring ambient relative humidity is not enough to prevent mold growth. At the surface of a cold wall relative humidity is higher than elsewhere in the room, and may locally reach a level that facilitates mold growth. Similarly, a water leak may also cause humidity at the surface of a wall to be a lot higher than room humidity.

Unlike a regular hygrometer, the DampGuard measures humidity where it matters: at the surface of a wall as opposed to measuring the humidity of ambient air.

The DampGuard uses the ROTRONIC HYGROMER^® humidity sensor – one of the best relative humidity sensors available today. The unique design of the DampGuard ensures that the humidity sensor measures the boundary layer or air that exists in the immediate vicinity of the wall, i.e. at a distance of just a few fractions of an inch, where it truly matters for mold growth.

PLEASE, NOTE THIS: Mold can grow in hidden places. Examples are the back side of dry wall, wallpaper, or paneling, the top side of ceiling tiles, the underside of carpets and pads, etc. Further examples include areas inside walls around pipes (with leaking or condensing pipes), the surface of walls behind furniture (where condensation forms), inside ductwork, and in roof materials above ceiling tiles (due to roof leaks or insufficient insulation).

The DampGuard measures relative humidity on the side of the wall or surface to which it is attached. Depending on the situation, it may be unable to provide a correct indication of the risk of mold growth on the other side of the wall or surface.