Damp proofingin West Londondone once, properly

The classic West London job is a ground-floor wall in a terrace showing a tide mark roughly 600mm to a metre up, with hollow plaster and white salt bloom. Where the survey confirms a failed or missing damp proof course, we inject a new chemical DPC into the mortar bed using a Sovereign or Wykamol system, then remove the contaminated plaster back to masonry and replace it with a salt-retardant render and skim.

Skipping the replaster is the single most common reason a damp proofing job fails. The old plaster holds hygroscopic salts that pull moisture from the air indefinitely, so the wall keeps looking damp even after the DPC works perfectly.

We check for bridging before recommending injection. If a patio, path or render coat is carrying moisture past the DPC, the cheaper and more honest answer is to correct that first.

Damp that tracks the weather is water crossing the wall. On West London properties the usual culprits are eroded lime mortar joints, cracked or debonded cement render, defective sills without drip details, perished sealant at window frames, and gutters or downpipes discharging onto one narrow strip of wall.

End-of-terrace flank walls are the worst affected because they take the full force of south-westerly driven rain with nothing in front of them. Repointing in an appropriate mortar, replacing spalled bricks, repairing render properly and applying a breathable water-repellent treatment where suitable is the durable route.

Where cracking has opened a path for water, often at bay junctions or over openings, helical brick stitching restores the masonry rather than simply filling the crack.

Plenty of West London houses have a cellar or a vaulted space under the front bay, and most were never intended to stay dry enough for habitable use. Turning one into a utility room, gym or study means a proper structural waterproofing design: cementitious tanking bonded to sound masonry, or a cavity drain membrane with perimeter drainage, a sump and a pump where gravity discharge is not available.

We detail junctions, service penetrations and the floor-to-wall return carefully, because that is where basement waterproofing leaks. Waterproof paint is not a solution, it cannot resist water arriving under pressure.

Damp is one of the most common items flagged in West London homebuyer surveys, and it stalls sales while buyers, lenders and vendors argue about cost. A free survey gives you the actual cause and a written fixed price, which is usually enough to restart the conversation.

Where we carry out the treatment, the 10-year workmanship guarantee and the 10-year QANW insurance-backed guarantee provide the paperwork a buyer's solicitor or surveyor will ask for. Building works carry a 6-month workmanship guarantee.

From West London we also cover the wider capital, Middlesex, Brent, Watford, Slough, Buckinghamshire, High Wycombe and Surrey, so a property near a boundary is never a problem.

If a sale, remortgage or tenancy start date depends on the report, say so when you call and we will tell you honestly whether the timescale works.