Surface water on flat coastal ground
East Preston sits on the coastal plain between the South Downs and the Channel, and the parish has had first-hand experience of water with nowhere to go. The neighbourhood plan records two localised flooding events in 2012, when some residents of Sea Lane had to leave their homes, and notes that West Sussex County Council has since carried out CCTV surveys, cleaned the surface water pipe and gullies, and done major work to the outfall and ditch. It also says drainage pipes, ditches and culverts need surveying and improving across the parish, especially on the two private estates, Angmering-on-Sea and Willowhayne, where ditches are the responsibility of riparian owners. Among residents' concerns, the plan lists the future effect of gradually rising sea levels.
For a homeowner, the practical point is that water pooling against walls, blocked gullies and neglected ditches all feed damp into the base of a house. Sorting out drainage around the building is often the first fix, before anything is done to the walls themselves.
The three common causes
Rising damp leaves a tide line, salts and crumbling plaster at the bottom of a wall, and is often the result of a failed damp proof course, or one bridged by a raised path, patio or flower bed. Penetrating damp comes in through cracked render, failed pointing, leaking gutters or gaps around windows, and shows as patches that spread after rain. Condensation produces black mould on cold surfaces: window reveals, corners, behind wardrobes and on the ceilings of rooms kept cool. It tends to appear where some rooms are left unheated and in flats with poor ventilation.
Old flint and newer walls
The oldest cottages along The Street and Sea Road have flint and brick walls, often with no damp proof course at all, and they need to breathe. Sealing them in hard cement render or impervious plaster usually makes damp worse rather than better. On these walls the remedy is often about removing whatever traps moisture, improving drainage and ventilation, and re-plastering in breathable materials. On twentieth-century houses and bungalows where a damp course has failed, an injected damp course in the mortar at the base of the wall, with the salt-damaged plaster replaced above it, is the standard approach. Cellars and other below-ground rooms need tanking, with a waterproof render or a cavity drain membrane.
Before you get in touch
Make a note of when the damp shows: after heavy rain, during a cold spell, or all year round. Then look outside at the same wall for blocked gullies, soil or paving heaped against the brickwork, dripping gutters and cracked render. Houses close to the beach take wind-driven rain on their seaward walls, so penetrating damp there often starts with a small crack in the render or a gap around a window frame. Photos of both sides of the wall help us judge what is happening before we visit.
Putting the walls back
Treated walls need making good, and because plastering is our trade, we finish them ourselves: float and set in East Preston for walls taken back to masonry, and rendering in East Preston where the outside face has failed. See our damp proofing and mould prevention page for more, or our East Preston page for all our local services. Call 07824 165672 for free, no-obligation advice.
