Note all areas of damp

Typically a brown stain results from water passing through a brick or over timber and is caused by:

  1. penetrating damp or
  2. a leak.

However, brown stains could be:

  • old and never painted over,
  • caused by rust, such as plasterer beading,
  • caused by condensation acting as a leak, 
    – such as insterstial condensation from a poorly ventilated loft.

  • Next steps

    Check for penetrating damp >

    Check for a leak >

    Check for metal >

    Check potential for interstitial condensation >

    If it is exclusively at the base of a wall > check profile

    If there is damp high up a wall or on another floor >

    Is there a horizontal band of damp

    Human don’t smell water. We smell mould which we associate with dampness. We sense humidity, such as when it is “close”.

    When there is mould go to the next step>

    If you have an anemometer (windspeed tester) test the airspeed exiting the building from the bathroom, kitchen and other wet rooms.

    Consider the need for ventilation in the property overall.

    Find out if the property has been damp-proofed.
    (Often there are tell-tale drill holes on the outside). 

    If it has then walls may not reveal the event of dampness.