Compare the main damp and moisture problems by their visible clues, timing and location. These pages are designed to help you narrow the cause — not jump straight to treatment.
Use the cards as a starting point. Several damp problems can look similar, so compare the full guide before assuming a cause.
A serious timber-decay fungus requiring reliable identification and control of the underlying moisture.
Open guide →Timber decay associated with persistently high moisture; the water source must be removed.
Open guide →Below-ground rooms can be affected by ground moisture, water ingress, drainage and condensation at the same time.
Open guide →Escaping water from supply pipes, wastes, seals, appliances or heating systems can mimic other forms of damp.
Open guide →Visible mould growth caused by persistent surface moisture; the moisture source matters more than the colour.
Open guide →Rainwater or external moisture entering through a defect in the roof, wall, opening or rainwater system.
Open guide →Low-level masonry moisture that needs evidence and careful exclusion of more common lookalikes.
Open guide →Moist indoor air forming water on colder surfaces — often windows, external walls and cold corners.
Open guide →Black mould, wet walls, peeling paint and white salts can all have more than one possible cause.
