Damp Proofing Fitzrovia

Our London office is on Fitzroy Street, so Fitzrovia is genuinely on our doorstep. The area takes its name from Fitzroy Square, whose Georgian terraces, partly designed by Robert Adam, still define the northern end of the neighbourhood. Around them, Charlotte Street, Cleveland Street, Great Titchfield Street and Rathbone Place mix Georgian and Victorian terraces with mansion blocks, mews, small office buildings, restaurants and shops, many of them with homes on the upper floors.

Almost every older building in Fitzrovia has a basement. Front basements with lightwells and vaults running out under the pavement are typical, and they are one of the most common sources of damp we see in W1T. Pavement vaults were built for storing coal, not for living or working in, and water gets in through the vault roofs, the junction with the pavement above and the surrounding ground. Converting these spaces into offices, kitchens, bedrooms or storage needs a waterproofing system designed to BS 8102, usually a cavity drain membrane with a drainage channel and, where needed, a sump and pump.

Above ground, the Georgian and Victorian terraces have solid brick walls, lime mortars and hidden roofs behind front parapets. Parapet gutters, valley gutters and old lead work are frequent causes of penetrating damp in top floor flats, while failed pointing, cracked stucco and defective rainwater pipes let water into the front and rear elevations. Because many of these defects are out of sight, damp often appears well away from where the water is actually getting in.

Fitzrovia's mixed use buildings bring their own issues. Restaurants and kitchens at ground and basement level generate large amounts of moisture, and where extraction is poor, condensation and mould can affect neighbouring rooms and the flats above. Leaks from upper floor bathrooms and kitchens are another common cause of damp in the flats below.

Timber is another concern in the older terraces. Floor joists and beam ends built into damp external walls, and timbers in poorly ventilated basements and under stairs, are vulnerable to wet rot, and we occasionally find dry rot spreading behind panelling or under floors in buildings that have been empty or neglected. Treating the decayed timber is only half the job. The moisture source has to be dealt with too, or the decay will return.

Mews houses behind the main streets deserve a mention as well. Many were originally stables and coach houses, built with ground floors close to or below the level of the cobbled mews, and their walls are often damp at low level where the surface outside sits higher than the floor inside.

Much of Fitzrovia lies within the Charlotte Street and Fitzroy Square conservation areas, and many buildings are listed. That means repairs have to suit the historic fabric. We favour breathable lime based plasters and renders, careful masonry and lead repairs, and drained membrane systems below ground that can be installed without damaging original structure, and we can provide reports to support any consent that is needed.

For residents, landlords, managing agents and commercial occupiers, the key is an accurate diagnosis. Our surveys combine moisture readings, salt analysis and thermal imaging with a close look at the building's construction, so we can tell the difference between groundwater, rain penetration, leaks and condensation and recommend the right repair.

Being based on Fitzroy Street means we can often survey in Fitzrovia at short notice, and we know the area's buildings, their quirks and their management companies well.