Damp, mould and condensation

This type of dampness will only be found on external walls or, in the case of roof leaks, on ceilings.

It only appears because of a defect in the structure of the home, such as missing pointing to the brickwork, missing roof tiles, loose flashing or leaking gutters.

These defects then allow water to pass from the outside to the inner surfaces. Penetrating dampness is more noticeable after a period of rainfall and will normally appear as a 'damp-patch' which looks and feels damp to the touch. "Tide marks" will be left, even in periods of dry weather. 

Mould may be seen on areas of penetrating dampness but not in all cases as the dampness can contain salts picked up when passing through the wall, which may prevent the growth of mould.

If defects are found in the property, a builder will need to carry out the repairs. Tenants should ask their landlord to investigate further.