Guide
Independent damp survey vs a free survey: which one to book
Updated
The cheapest survey and the best-value survey are rarely the same one. Here is what each kind actually is, who is paying the surveyor, and when a free survey is genuinely fine.
Who is paying the person inspecting your wall?
A free damp survey is almost always carried out by a damp-proofing or timber treatment company. The visit costs you nothing because the company's income comes from the treatment work it quotes afterwards. That is not a scam, it is a sales model, but it means the person diagnosing your damp is rewarded for finding damp that needs their product. An independent damp survey reverses the incentive: you pay a fee, typically £150–£400 in 2026 quotes, and the surveyor sells nothing else, so the report has no reason to favour injection creams over a leaking gutter.
What £150–£400 actually buys
- An hour or more on site, inspecting inside and out: ground levels, gutters, pointing, ventilation, sub-floor where accessible.
- Readings in context: moisture meter profiles, often a hygrometer for condensation risk, sometimes samples for salts analysis on bigger jobs.
- A written report stating the cause (condensation, penetrating damp, a leak, rising damp, or a mix), what to fix, and in what order.
- Ammunition: if you're buying, a written independent diagnosis supports renegotiation; if a treatment company quoted you thousands, it confirms or kills that quote.
When a free survey is fine
If you already know what the problem is and you're simply pricing treatment, free surveys from two or three treatment companies are a reasonable way to collect quotes, treat them as quotes, not diagnoses. The time to insist on independence is when the diagnosis itself is the question: unexplained damp, a big quoted bill, a purchase decision, or a dispute with a landlord, freeholder or insurer.
Picking an independent surveyor
- Ask directly: "Do you or any connected company carry out damp-proofing work?" Independent means no.
- Look for qualifications and memberships: RICS surveyors with damp experience, or Property Care Association qualified surveyors (CSRT/CSTDB) who work on a consultancy-only basis.
- Expect a fee quoted up front and a written report included. A verbal opinion is not a survey.
- For pre-1919 solid-wall buildings, ask about experience with older construction, they behave differently from modern cavity walls and are the most misdiagnosed.
Prices above are typical 2026 quote ranges and vary by region and property size. Get exact prices from independent surveyors covering your postcode.