About
I don't survey your house. That's the point.
Three people have looked at the same wet wall and told you three different things. One says rising damp and a new damp-proof course. One says condensation and a fan. You cannot check any of it, because the person explaining the problem is also the person quoting for the fix. I do no work, hold no clipboard, and take no fee for sending you anywhere. That is the only reason I can tell you when the answer being pushed at you is the wrong one.
Why the three explanations don't agree
Not because anyone is lying to you. A firm that installs damp-proof courses looks at a wet wall and sees the job it does. A firm that fits ventilation sees a different one. Both are looking honestly and arriving somewhere useful to themselves.
That is a fact about how the trade is set up, not an accusation about anybody in particular. It still leaves you holding two quotes you have no way to judge. Every page here starts from the same rule instead: find the source or it comes back.
- Damp only: the three kinds, the tells that separate them, and what each fix really does.
- Cause first: if a treatment only covers the symptom, the page says so.
- What to ask: you are about to have a conversation you are unequipped for, so every page arms you for it.
Even the survey you pay for may not settle it
A RICS Home Survey Level 2 is worth having. It is not a damp diagnosis, and RICS has never said it was. Its own published description of the service says the surveyor uses a damp meter and "does not force or open up the fabric of the building". Where the surveyor cannot reach a conclusion with reasonable confidence, the designed outcome is a recommendation for further investigation.
BS 6576 is blunter. Surface measurements cannot alone give proof of rising damp, and the evidence has to come from inside the depth of the wall. So a survey that flags damp and passes you on is not failing you. It is routing you, exactly as designed.
The cheapest thing waiting at the end of that route is a free survey, and free damp surveys are carried out by companies that quote for the treatment. Knowing that before you pick up the phone is worth more than anything else on this website.
Where the figures come from
No price, timescale or moisture reading on this site is mine. Each one comes from a named source with a date on it, so you can go and check it yourself. A British Standard, a published cost guide, a manufacturer's own instructions. Where two sources disagree, the page prints both instead of quietly picking the tidier number. When the honest answer is "it depends", the page tells you what it depends on.
What I can't do from here
I cannot tell you what is wrong with your wall. Nobody can work that out from a photograph, and a website pretending otherwise is worth less than nothing. I cannot price your job either. A page can say what a type of work costs and what moves that number up or down. Sometimes the honest next step is an independent inspection by someone with nothing to sell you, and the page says so even though that ends it.
Who runs this site
This site is operated by That Guy, 71-75 Shelton Street, Covent Garden, London, WC2H 9JQ, United Kingdom. Damp advice touches your health and a four-figure spending decision, so you are entitled to know who is publishing it before you act on any of it.
Four figures is not a scare number. A whole-house damp-proof course plus the re-plastering afterwards is published at £1,500 to £4,000 by bestbuilders.co.uk, dated August 2026, and that is one of two guides this site quotes because they do not agree with each other.
Nothing here is sponsored. No damp-proofing company pays for a mention, none sees a page before it goes up, and none has any say over what it says. Where a product link ever earns me a commission, the page carrying it tells you so, right where the link sits. That is the only money on this site, and it buys nobody an opinion.
Still can't tell which one is right?
You have read this far, so the wall is still bothering you. Send me what you have been told and what you can see. I cannot diagnose it from a message, but when the same question keeps landing, it gets a proper page on the site.
Send me the details