Your questions, answered

Tide marks low on a wall, salt deposits and crumbling plaster often point to moisture rising or getting in from outside. Black spotting around window reveals and on cold corners is more typical of condensation. The two can appear together in the same room, so the pattern, height and timing of the marks matter more than any single sign.

Usually not for long. Fresh paint hides the stain but leaves the source alone. A leaking gutter, bridged damp course, cracked render or poor ventilation will keep feeding moisture into the wall, and the marks tend to return, sometimes with mould or decayed timber behind them.

The surveyor walks the inside of the property checking walls, floors and ceilings, takes moisture readings, and looks outside at gutters, downpipes, pointing and ground levels. On a damp and timber survey, floor joists and roof timbers are checked too. A written report follows, setting out what was found and the likely cause.

A specialist damp surveying company visits the property, takes the readings and writes the report. Any treatment it recommends is also carried out by that company. This website only handles the booking, so nobody from here inspects or treats your home.

Each survey is booked at a set price, and you see that figure before you confirm. Prices differ between survey types, because a CCTV drain survey needs different equipment and time from a condensation or mould survey. Pick the survey that matches your problem and the booking page shows what it costs.

A Level 2 survey normally notes visible signs of damp and may take a few meter readings, but it rarely investigates the cause in depth. Where it flags a concern, a pre-purchase damp survey looks closer before you commit. Mention your completion date in the booking notes.

A mould survey or condensation survey usually fits, depending on whether the growth is spread across rooms or tied to one cold wall. Note in the booking which rooms are affected, when the mould appears and whether the tenant dries washing indoors. That helps the surveyor plan the visit.

It depends on the size of the building, how many rooms are affected and how easy it is to reach lofts, subfloors and outside walls. The visit date depends on the surveying company's diary, which is confirmed once the booking goes through.

A general builder may repair the visible damage without pinning down why the wall got wet. A damp surveyor concentrates on diagnosis, separating rising damp, penetrating damp and condensation, which each need a different fix. Getting the cause right first stops money going on the wrong treatment.