Rising Damp Treatment in Brighton & Sussex

Rising damp occurs when groundwater is drawn upward through porous masonry by capillary action. In a healthy building, a physical damp-proof course (DPC) — typically a layer of slate, bitumen felt, or engineering brick — prevents moisture from climbing above floor level. When this barrier fails, is missing, or has been bridged, water can rise through the wall to a height of around one metre, carrying dissolved ground salts with it.

Brighton and the surrounding Sussex towns contain thousands of Victorian and Edwardian terraced houses, many of which were built with slate DPCs that have cracked or deteriorated over more than a century. Flint-walled cottages and older Georgian properties may have no DPC at all. In these buildings, rising damp is a genuine and well-documented structural issue that worsens over time if left untreated.

The salts deposited by rising moisture — primarily nitrates and chlorides — are hygroscopic, meaning they absorb moisture from the air even after the source of rising damp has been addressed. This is why simply drying out a wall is not enough; contaminated plaster must be removed and replaced with a salt-resistant specification to achieve a lasting repair.

It is worth noting that rising damp is frequently misdiagnosed. Condensation, penetrating damp, and high external ground levels can all mimic its symptoms. That is why we always carry out a proper survey with calibrated instruments and salt analysis before recommending any treatment.

Once our survey confirms genuine rising damp, we install a new chemical damp-proof course by injecting a silicone-based cream into a series of precisely drilled holes at the base of the wall. The cream diffuses through the masonry and cures to form a continuous water-repellent barrier that prevents further capillary rise. We use BBA-certified products and follow PCA best-practice guidelines for hole spacing, depth, and injection pressure.

After the DPC is installed, we remove all salt-contaminated plaster to a height of at least 300 mm above the highest point of visible dampness. The exposed masonry is treated with a salt-inhibiting render before we apply a renovating plaster system designed to cope with any residual salts as the wall dries out. This two-stage approach — barrier plus replaster — is essential for a long-lasting result.

All rising damp treatments carry our 20-year written guarantee, backed by our PCA membership. We provide a detailed specification before work begins so you know exactly what to expect, and we leave every property clean and tidy at the end of each working day.