By the Sleak Property Services team ·
Blackpool has thousands of Victorian and Edwardian terraces in North Shore, Layton, South Shore and around the town centre. They're solid houses, but they were built before cavity walls and damp-proof membranes, and they sit in one of the wettest, windiest spots in the country. Damp is the most common problem we're asked about.
Short answer: most damp in these houses is condensation or water getting in from outside, not rising damp. The fix depends on which it is, so diagnose before spending money.
Condensation
Condensation happens when warm, moist air from cooking, showers, drying washing and breathing hits a cold surface and turns back into water. It's the most common cause of mould in homes.
- Black mould in corners, behind furniture and around window frames
- Water running down windows in the morning
- Worse in winter, in bathrooms and kitchens, and in bedrooms with the door shut
- Often on outside walls and ceilings rather than low down
The fix is ventilation and heat: working extractor fans in the kitchen and bathroom, trickle vents open, lids on pans, washing dried outside or near an open window, furniture pulled slightly away from outside walls, and the house kept evenly warm rather than heated in bursts.
Penetrating damp
Penetrating damp is water getting in from outside. In a coastal terrace, the usual culprits are blocked or leaking gutters, cracked render, worn-out pointing, failed sealant around windows, and slipped slates or flashings around chimneys.
- A damp patch that gets worse after heavy or wind-driven rain
- Patches at any height, often below a gutter joint, window or chimney breast
- Stained or bubbling plaster and peeling paint on one area of wall
Find where the water is coming in and fix that first. Repairing the gutter, pointing or render, then letting the wall dry out before replastering and redecorating, solves most cases for good. Plastering over a wet wall without fixing the cause just moves the problem.
Rising damp
Rising damp is ground water soaking up through the bottom of a wall. It's real, but it's much rarer than it's often said to be. Signs are a tide mark and damp plaster up to about a metre above the floor, with salts on the surface, on ground floor walls only.
Before agreeing to an injected damp-proof course, rule out the more common causes: ground or path levels outside that sit higher than the inside floor, a blocked air brick, rendered plinths trapping water, or a leaking pipe. Fixing those is often all that's needed.
For landlords
Damp and mould is one of the hazards councils assess under the Housing Health and Safety Rating System, and it's a common reason for tenant complaints and enforcement. Respond to reports quickly, find the cause, fix it and keep dated photos and invoices. Our guides for landlords cover end-of-tenancy checks and repairs in more detail.
Common questions
How can I tell if damp is condensation or rising damp?
Condensation usually shows as black mould in corners, on ceilings and around windows, and is worse in cold weather. Rising damp only affects ground floor walls, up to about a metre high, often with a tide mark and white salts.
Can blocked gutters cause damp inside?
Yes. Water overflowing onto the same section of wall soaks through solid brick walls. It's one of the most common causes of damp patches upstairs in older terraces.
Should I replaster a damp wall straight away?
No. Fix the cause first and let the wall dry out, otherwise the new plaster will stain and fail. Drying can take weeks or months on a solid wall.