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Penetrating damp

Penetrating damp is a type of moisture problem that occurs when water infiltrates a building from external sources, such as rain or groundwater.

Damp and mould example of penetrating mould

This can happen due to a variety of reasons, including:

Damaged roofs or gutters: Leaks or blockages in roofing materials or gutters can allow water to seep into walls.
Cracks in walls: Structural cracks in external walls can let moisture enter.
Poorly sealed windows and doors: Inadequate sealing around windows and doors can lead to water penetration.
Rising groundwater: High water tables can contribute to moisture seeping into lower parts of walls.

Signs of penetrating damp may include damp patches on walls, mould growth, peeling wallpaper, and musty odours. Unlike rising damp, which originates from the ground, penetrating damp comes from the outside and can affect both the interior and exterior of a building. Addressing the source of the moisture is essential for remediation.