Damp Proofing Brixton

Brixton runs from the busy town centre around Electric Avenue and Acre Lane up Brixton Hill towards Streatham, and east towards Herne Hill. It sits on London Clay, with the land falling gently from Brixton Hill down towards the town centre and Stockwell. That slope, and the lost river that once ran along it, shape many of the damp problems we see in SW2 and SW9.

The River Effra flowed north through Brixton on its way from Norwood to the Thames at Vauxhall. Effra Road still follows part of its course. The river was put into culverts in the 19th century, but streets along the old valley still sit lower than their surroundings and collect surface water and groundwater after heavy rain. Cellars and ground floor rooms on these streets are more prone to damp.

Most of Brixton's housing was built between the 1850s and 1900s, when the railways arrived and fields became streets of Victorian terraces and large villas. Many of the bigger houses on Brixton Hill, Brixton Water Lane and around Josephine Avenue have since been converted into flats. The walls are solid brick with no cavity, and the original damp proof courses are now well over a century old.

Rising damp is common in these terraces. Slate or bitumen damp proof courses crack and break down over time, and they are often bridged by raised front paths, rear patios and rendered plinths. The signs are tide marks, salt staining and crumbling plaster along the bottom of ground floor walls, especially in hallways and front reception rooms.

Penetrating damp is just as frequent. Bay roofs, parapet walls, valley gutters and chimney stacks let rain into solid walls when flashings fail or gutters block. Many Brixton chimney breasts show brown stains because flues were sealed without being capped and vented. We trace each leak with moisture readings and thermal imaging before recommending any repair.

Brixton also has a large number of purpose built flats, from Victorian mansion blocks to post war estates. Condensation and black mould are the most common complaints in these homes, caused by cold walls, small kitchens and bathrooms without extraction, and drying washing indoors. Better ventilation usually fixes the problem, and we measure the walls first to rule out rising or penetrating damp.

Under the floors, most Victorian houses in Brixton have suspended timber floors that rely on air bricks for ventilation. Rear extensions, raised gardens and blocked vents cut off that airflow, and damp joists and wet rot develop out of sight. We check the subfloor void on every survey where floors are timber, because that is often where the most costly damage starts.

Landlords make up a large share of our Brixton work. Under current housing standards, damp and mould in rented homes have to be investigated and dealt with promptly, and a written survey report gives landlords and letting agents a clear record of the cause and the fix. We work with tenants in place and arrange access around them.

Brixton is in the London Borough of Lambeth, and several areas, including Brixton Town Centre and Josephine Avenue, are conservation areas. Internal damp treatments rarely need planning permission. Every survey is carried out by a CSSW and CSRT trained specialist, and you receive a written report with photos, the cause and the recommended fix.