Maintenance
A damp patch that appears after rain.
Where the stain sits, and whether it follows the weather, tells you which trade to phone. A price for a damp course is the wrong first spend when the water is coming through the roof.
Checked 13 October 2026. For homes in England. This page does not inspect the wall. The Malta directory is a separate list.
More than one cause can be true in the same house. Use the pattern to choose who to phone. The diagnosis is theirs, after a visit.
High on the wall, or on the ceiling, after rain
A patch that darkens during rain and fades when the weather dries, especially on a top-floor ceiling, in a chimney breast, or under a window, is the pattern of water getting in. Typical routes are a slipped tile or slate, a split flashing, a blocked gutter, a failed flat-roof covering, or a frame that no longer sheds water.
Phone a roofer for that pattern. The roofing list includes London and Manchester. What a covering price is usually made of, including scaffold, is what sits inside a price for a new roof covering. A chemical damp course injected at the bottom of the wall does not stop water arriving from above.
Water you can see running down the outside, before a stain appears indoors, is a separate choice of who to phone. That note is water sitting against the house after the rain.
If the stain is around a bath, a shower, or a pipe you can see dripping, the trade is plumbing, on the plumbing and heating list. A roof quote will not repair a failed seal in a bathroom.
Low on a ground-floor wall, including in dry weather
A tide mark near the floor, sometimes with white salts in the plaster, that is still there after a dry week, is the pattern associated with moisture rising from the ground. That is the point to ask for a survey before you accept an injection price. The survey is there to separate rising damp from a high outside ground level, a bridged damp course, or a leak you have not seen.
Published treatment bands, and the plaster they leave out, are in what sits inside a price for damp treatment. The local damp list large enough to open as a set is London. You phone the business yourself.
Black mould in a cold corner, worse in winter
Mould on a cold outside wall, behind a wardrobe, or in a bathroom that stays wet, often tracks how the room is heated and ventilated. It can get worse in winter without any rain. That pattern is a reason to look at ventilation and how the room is used before you pay for a new damp course. Who to phone for that cold-wall pattern, including when a social landlord in England already has a clock running, is black mould on a cold wall when the heating stays low. If you are unsure which pattern you have, say so when you phone, and ask whether the visit is a survey or a treatment. The two are priced separately in the published guide.
Questions on this stain
The stain appears after heavy rain, high on the wall. Who do I phone?
Start with a roofer. A patch that tracks the weather, on a ceiling or high on a wall, is often water from a covering, a gutter, a flashing or a window. A chemical damp course does not repair that leak.
The mark is low on a ground-floor wall and it is there in dry weather. Is that the same job?
That pattern is the one people associate with rising damp. A survey comes before an injection price. The published treatment bands leave out plaster, decoration, drying and the survey itself.