Penetrating damp is rainwater crossing the wall from outside, often after weather and at any height. It is for houses and smaller buildings in England, Scotland, and Wales where the stain lines up with a gutter, joint, render crack, or flashing. Send the quote form or WhatsApp with a photo and the postcode.
Penetrating Damp Solutions
Water crosses the wall horizontally through cracked pointing, failed render, open joints, a leaking gutter, or a flashing. It is not moisture rising from the ground.
The repair is the defect, not a chemical damp-proof course. A new course in the mortar bed does not stop rain hitting a cracked wall.
The survey finds the entry point. The quote is for that repair, then time for the wall to dry. Internal plaster is renewed only where it has broken down.
A tide mark with salts on the ground floor may be rising damp. Black mould on a cold bedroom wall is usually condensation. Those are different visits.
Penetrating Damp Solutions
Open joints and soft pointing let rain sit in the outer leaf. Repointing is the repair when that is the path.
Cracked or hollow render holds water against the wall. Painting the crack does not stop the path behind it.
A leaking gutter or a joint that discharges onto the wall is a common cause and a smaller job than “damp proofing” implies.
Failed lead or soakers show as damp on a chimney breast or at a roof junction, often well above the ground floor.
A cracked sill or an open seal lets rain into the reveal. The stain sits under the window, not as a tide mark along the floor.
Older solid brick has no cavity to drain into. Rain soaks the thickness when the face is open.
We look for a defect on the outside that lines up with the wet area inside.
We look for a defect on the outside that lines up with the wet area inside.
Salts, ground levels, and pipework are checked so rain is not blamed for a different cause.
The quote names the gutter, pointing, render, or flashing that is actually letting water in.
Sound plaster is left.
A solid brick wall about 230mm thick commonly takes months to dry after the moisture is stopped.
The treatment named in the written quote carries a 30-year guarantee.
The price follows the defect. A gutter joint is not the same quote as repointing an elevation or renewing render. Waterproof paint on the inside is not a substitute, and it is not how we price the job. The written quote lists the outside repair and any plaster that has to come off.
Questions that decide whether this is the right job.
No. The water is coming through from outside. The course in the wall does not close a crack, a gutter, or a flashing.
That pattern fits water crossing the wall. Rising damp does not wait for a storm, and condensation does not suddenly soak one patch of an outside wall.
A tanking paint on the inside face traps the water in the wall. The outside defect still has to be closed.
A solid brick wall about 230mm thick commonly takes months to dry after the moisture is stopped. Thicker walls take longer. Do not finish with a vinyl paint while the wall is still drying.
Tell us the floor, whether it follows rain, and the postcode. The quote follows the survey.
Get Your Free QuoteA damp survey with moisture meters and thermal imaging, so the cause is known before any work.
Learn more about Damp Survey & Moisture ReportRemedial work where cavity insulation is part of the damp, quoted after the wall is surveyed.
Learn more about Cavity Wall Insulation RemedialGroundwater travels up through brickwork when the damp-proof course is missing or has failed.
Learn more about Rising Damp TreatmentSurveys run in Kent, Cardiff, and Glasgow, and in the other counties and towns on the areas page.
Name the room, the floor, and what the wall is doing. WhatsApp takes the same details.