Brick is not completely waterproof
Masonry absorbs and releases moisture. A sound wall is designed to manage exposure, but persistent driving rain, cracks, saturated surfaces or defective details can allow water to reach inside.
Solid and cavity walls differ
Older solid walls may rely heavily on appropriate materials and drying. Cavity walls are intended to manage rain penetration differently, keeping the inner leaf relatively protected. Defects within cavities can undermine that separation.
Where defects occur
Look around windows, sills, coping stones, parapets and changes in roof level. Failed pointing, inappropriate hard mortar, damaged render or blocked cavity trays can contribute. The pattern after wind-driven rain is useful evidence.
Check before coating
Water-repellent products are sometimes proposed as a first remedy. They may be unsuitable for some wall types or conceal defects. Repairing the source and using compatible materials is often more important than applying a surface coating.
Why the damp patch is displaced
Water can follow mortar joints, insulation, timbers or cavities before it becomes visible. The wet area indoors may not be opposite the point of entry, which is why a methodical exterior inspection is useful.
Plan suitable repairs
A competent survey should identify entry routes, wall construction and exposure. Repair gutters, flashings, pointing and detailing where defective, then allow time for the wall to dry. Monitor before redecorating.
Keep dated photographs and notes of any changes. They can be useful when explaining the issue to a surveyor or contractor. If there is active water near electrics, an unstable ceiling, or a floor that appears unsafe, arrange prompt professional help rather than waiting to see whether the problem improves.
Need help from a local damp specialist?
Look for a suitable local professional and explain the symptoms clearly. You can use an external trade-matching service to request quotes; check credentials and the proposed diagnosis before agreeing to work.
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