Damp and Mould Solutions UK - Professional Damp Proofing & Mould Remediation

What is Penetrating Damp?

Penetrating damp, or lateral damp, is the presence of moisture in a building that has entered from the outside, through the walls, roof, or floor. Unlike rising damp, it is not limited to the ground floor and can appear at any level of a property. It is typically caused by building defects or external maintenance issues that allow water to breach the property's defences.

Common causes include faulty guttering, damaged roofing, cracked render, porous brickwork, or defective seals around windows and doors. If left untreated, it can lead to significant structural damage, timber decay, and mould growth.

Water stains on a ceiling from penetrating damp

Damp patches on ceilings are a common sign of penetrating damp.

Cracked and damaged external render on a house wall

Defective render or brickwork allows rain to soak through.

Common Signs of Penetrating Damp

Identifying penetrating damp involves looking for localised patches of damp that can appear at any height on your walls. Key signs include:

Localised Damp Patches

Unlike the uniform pattern of rising damp, penetrating damp causes distinct, often blotchy, patches of moisture that can appear anywhere on walls or ceilings.

Worse After Rainfall

The damp patches often appear or become noticeably worse after periods of heavy or wind-driven rain.

Damaged Plaster & Decor

Similar to other forms of damp, it will cause plaster to blister, paint to peel, and can lead to the growth of black mould.

Musty Smell & Spore Growth

A persistent damp, musty odour and the appearance of mould or mildew are common secondary signs.

Our Solution: Identify, Repair, and Protect

Treating penetrating damp requires a two-stage approach. First, we must accurately identify the source of the water ingress. Second, we carry out the necessary repairs and apply protective barriers to prevent future issues.

Repairing faulty brickwork and re-pointing is a key step.

A worker applying a clear waterproof coating to a brick wall

Breathable waterproof coatings protect the walls from rain.

Our Process Can Include:

Thorough Survey: Our experts conduct a detailed external and internal survey to pinpoint the exact cause of the problem, whether it's faulty brickwork, leaking pipes, or roofing issues.
External Repairs: We carry out all necessary external repairs, such as re-pointing brickwork, repairing render, clearing or fixing gutters, and sealing window frames.
Waterproof Coatings: For porous brickwork, we can apply a high-performance, breathable waterproof coating. This clear treatment stops water from being absorbed by the bricks while still allowing the wall to breathe and release internal moisture.
Internal Restoration: Once the external issue is resolved, we address the internal damage, which may involve hacking off damaged plaster, treating the area for mould, and re-plastering with specialist materials.

Penetrating Damp Solutions