How Much to Charge for a Damp Proofing Job in 2026

What a damp-proofing quote needs to include

"Rising damp treatment — £950" tells a customer nothing about what was actually found, or why that's the fix. Cover these ten things and the quote reads as a diagnosis with a price attached, not the other way round:

1. 1A written diagnosis, not just a price — the moisture readings taken, any hygroscopic salts test result, and the specific cause identified (rising damp, penetrating damp, condensation, or a bridged or failed existing DPC).
2. 2Property age and wall construction — solid brick or stone (commonly pre-1919) versus cavity — since this changes which treatments are even appropriate.
3. 3The exact treatment specified and why: chemical injection DPC, physical DPC replacement, electro-osmotic system, tanking, or — just as often the right call — no DPC at all, with ventilation and lime-plaster repairs instead.
4. 4Wall run length in metres for DPC injection, or area in m² for tanking and re-rendering, priced as their own lines.
5. 5Replastering spec — salt-retardant renovating plaster or breathable lime plaster — since contaminated old plaster almost always has to come off regardless of which DPC method is used.
6. 6Ventilation works included, such as clearing or adding airbricks — blocked sub-floor ventilation is one of the most common real causes behind a 'rising damp' call-out.
7. 7Whether external ground levels, paths or flower beds are bridging the existing DPC, and whether lowering them is included in this quote or excluded as the customer's own job.
8. 8Guarantee length and whether it's insurance-backed, naming the scheme (PCA Promise, GPI or equivalent) rather than just 'guaranteed'.
9. 9PCA membership or other trade accreditation, named on the quote, not just implied.
10. 10Payment terms and a valid-until date.

Not every damp job needs the same treatment

The headline price people search for is almost always "chemical DPC per metre." The harder, more valuable part of this trade — and the part that actually protects you from a comeback — is working out whether that's even the right job.

What's actually causing it — before you price anything

BS 6576:2005+A1:2012, the British Standard covering diagnosis of rising damp and installation of chemical damp-proof courses, is explicit that a proper diagnosis has to come before a treatment is specified — not a handheld moisture meter reading taken on its own. Those meters measure electrical conductivity, which rises with dissolved salts and other contaminants in the wall as well as with water itself, so a high reading can just as easily mean old hygroscopic salts left behind by a previous damp episode, a cement-based plaster, or even foil-backed wallpaper — none of which is active rising damp. A proper diagnosis under BS 6576 means a moisture profile taken at different heights, a check of what the plaster and masonry are actually made of, and often a hygroscopic salts analysis before a chemical DPC is even on the table. Skip that step and the "diagnosis" is really just a sales conversation with a price at the end of it.

When a chemical DPC is the right call — and when it isn't

In a solid-wall property built before around 1919 — no cavity, often lime mortar and lime plaster — the far more common culprits behind a damp patch are penetrating damp through defective pointing or render, condensation from poor ventilation, or perfectly ordinary ground levels, paths or flower beds bridging an existing DPC that's actually still working. All three have cheaper, less invasive fixes than an injected chemical course, and all three get missed by a meter reading alone. SPAB's guidance is that there "should be a presumption against retrospective DPCs" in these properties, and that where a physical DPC genuinely can't be installed, only a chemical method with third-party certification (an Agrément certificate, in UK trade terms) should be considered — not any product off the shelf. None of this rules chemical DPC out of a quote. It means the quote should say which of these was actually ruled out first, and why the chemical method is the right remaining option for this specific wall.

What an insurance-backed guarantee actually buys the customer

An insurance-backed guarantee — the Property Care Association's PCA Promise and products like a GPI Guarantee are the common UK versions — is underwritten by an insurer, not just your own company's word. If the contractor who did the work stops trading, the customer can still claim directly against the policy, and the scheme's own network of approved contractors carries out the repair at no extra cost to them. Terms are typically offered in 10, 20 or 30-year bands with claim limits running from a few thousand pounds up to £500,000 on the largest policies. Mortgage lenders and conveyancing solicitors routinely ask for one by name — not just "a guarantee" — before releasing funds on a property with a history of damp treatment, which makes it close to a practical requirement on domestic DPC and tanking work, even without being a legal one.

How to price the work

UK damp-proofing prices vary by treatment, wall length and region, but these are a fair starting point for 2026:

• Damp survey & diagnosis: £150–£300, written report.
• Chemical injection DPC: £40–£60 per metre (silicone cream at the lower end, thixotropic gel and microemulsion a little higher).
• Re-plastering with salt-retardant renovating plaster: roughly £40–£50/m², usually needed regardless of DPC method.
• Physical DPC replacement (new course cut into the masonry): £1,000–£4,000 depending on wall length and access.
• Electro-osmotic DPC system: £1,200–£3,000.
• Basement/cellar tanking: £1,000–£2,000 for a small space, roughly £40–£80/m² depending on size and method (tanking slurry, membrane or waterproof render).
• A full job on a typical 3-bed semi — survey, DPC and re-plastering combined — commonly lands around £1,200–£2,000.
• Insurance-backed guarantee registration: typically a modest fixed add-on per job, well worth itemising rather than folding into the headline price.

A worked example

A Victorian terrace living room and hallway, diagnosed as rising damp after a proper moisture profile and salts test (not a meter reading alone), priced as separate lines rather than one round "damp treatment" number:

£1,635 for a diagnosed, treated and guaranteed job — noticeably more than the "£40-a-metre" headline figure a customer may have seen online, because that figure is the DPC injection alone, not the survey, the re-plastering, the airbrick clearance or the 20-year insurance-backed guarantee that makes the job mortgage-ready. Breaking it out like this is what lets a customer see exactly where the extra cost sits, rather than wondering why your number is double someone else's.

Five details that get damp-proofing quotes accepted faster

• Lead with the diagnosis, not the treatment. "Moisture profile and salts test completed — penetrating damp from a cracked render, not rising damp" reads as a professional opinion, not a sales pitch for an injection kit. It's also the one line that explains why the price isn't what a customer half-expected from a quick online search.
• Name the guarantee scheme, not just the word 'guaranteed.' "20-year insurance-backed guarantee via [scheme]" is a checkable claim a solicitor or mortgage lender can act on. "Fully guaranteed" on its own answers nothing when someone asks what happens if your company isn't trading in year twelve.
• Put the re-plastering on its own line, priced separately from the DPC. Customers comparing a £450 DPC quote against yours at £1,400 aren't always comparing like for like — if your figure includes stripping and re-rendering salt-contaminated plaster and theirs doesn't, say so plainly rather than letting the number alone do the explaining.
• Flag a pre-1919 solid-wall property before specifying a chemical DPC. A short note — "solid brick construction, checked ground levels and airbrick ventilation before considering a chemical DPC" — signals you didn't reach for the injection gun as a default, which is exactly the complaint that follows this trade around.
• State what's excluded as clearly as what's included. "Excludes lowering external ground levels — recommended but not quoted here" protects you from a comeback six months later when the damp returns because of something you flagged but weren't asked to fix.

The fastest way to do all of this

A single-room damp survey is easy enough to write up by hand. A job that mixes a diagnosis, a DPC method, re-plastering by area, airbrick works and an insurance-backed guarantee — and needs to show its working clearly enough that a mortgage solicitor is satisfied — is exactly where a vague verbal quote does the most damage to trust in this trade.

This is what QuoteRocket is for. Describe the job in plain English — "rising damp diagnosed in living room and hallway, 10m chemical injection DPC, hack off and re-render to 1m, clear 4 airbricks, 20-year insurance-backed guarantee" — and it turns that into a branded, itemised PDF quote in under a minute, with the diagnosis, treatment and guarantee kept as their own clearly labelled lines. Your customer accepts it with one tap on their phone, and an accepted quote becomes an invoice in one click.

Whichever way you produce the quote, the principle holds: diagnose before you specify, name the guarantee scheme rather than just the word "guaranteed," and show your working on an older property rather than defaulting straight to a chemical DPC. It's the difference between a quote that reads like the next cowboy story and one that gets forwarded straight to a solicitor without a second thought.

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