Start with the diagnosis, not the sale
Before looking at products or comparing quotations, ask why the wall is damp. Moisture travelling upwards through masonry, rain entering from outside and water collecting on cold surfaces call for different fixes. A company should explain how its findings lead to a particular recommendation, rather than treating every stain as the same problem.
Our types of damp guide gives you a starting point for that conversation. If you are unsure about a low patch or mould in a corner, read rising damp versus condensation.
Look for a survey that joins the evidence together
A useful assessment looks beyond the most noticeable mark. Inside, the affected surfaces and surrounding areas need examining. Outside, ground levels and possible routes for rainwater deserve attention. Moisture readings help describe the pattern, but ask how they have been interpreted alongside the building and its condition.
Ask for the suspected source, supporting observations and proposed action in writing. Where more than one cause is involved, the recommendation should separate them so you understand what each part of the work addresses.
Damp Pro and Co offers free, no-obligation damp surveys for homeowners. These include inspection inside and out, moisture readings, diagnosis, an honest recommendation and a written quotation.
Ask practical questions before choosing a contractor
When speaking to damp proofing companies, take a short list of questions and write down the answers. An explanation in everyday language is more useful than a product name on its own.
- What is bringing moisture into this wall, and what evidence points to that cause?
- What relevant training have the technicians received?
- Which treatment product or system is proposed, and why is it suitable here?
- Which parts of the job have a guarantee, and what does that document cover?
- Who removes damaged plaster, replaces it and leaves the wall ready for decoration?
Training and treatment are separate checks
Damp Pro and Co technicians are PCA trained and Safeguard Ltd trained, and we use a BBA approved damp proofing system. Ask any contractor about both the people doing the work and the proposed materials.
Recognise warning signs in the recommendation
Pressure to sign during the visit makes it harder to read the proposal or compare alternatives. Take time to check the details. A verbal description without a written quotation also leaves you unable to confirm which walls, preparation and finishing have been included.
Question a damp proof course recommendation if the explanation describes condensation but offers no evidence of rising moisture. Damp proof course treatment addresses moisture rising through suitable masonry; it does not prevent humid indoor air meeting a cold surface. Ask the contractor to explain that distinction in relation to the symptoms you have shown them.
A guarantee described only as a number of years is another reason to ask questions. Request the actual wording and connect it to the work being proposed.
Read the guarantee alongside the job description
A written certificate should identify the business issuing it, the property, the work covered and the period of cover. Look for a way to report a problem and any conditions affecting that process. Keep the document with the quotation so you can see how the covered work relates to the agreed scope.
Damp Pro and Co’s 20-year guarantee certificate is issued on completion of damp proof course work and payment. Guarantees for other work depend on the job. Discuss the relevant cover when reviewing your recommendation. Our damp proof course guarantee guide explains the questions worth asking before work begins.
Compare quotations for the same work
Place the proposals side by side and match the wall areas, preparation, treatment and finishing. One may describe injection alone while another includes taking off affected plaster and replacing it. Ask who handles skirting, furniture access and decoration, and have any agreed changes recorded before accepting.
Read about replastering after damp proofing to understand why the wall finish needs its own specification. Our damp proofing cost guide explains the factors that change the amount of work. A fair comparison begins with matching scopes, rather than choosing between totals for different jobs.
Book a free survey for your home
If you are looking for damp proofing contractors, start by having the moisture source investigated. Call Damp Pro and Co on 07803 253337 or freephone 0800 593 0300 to arrange your free survey. You can consider the findings and written quotation without committing to treatment.
Common questions
Should a damp survey be free?
Ask what the visit includes and whether there is any obligation attached. Damp Pro and Co offers homeowners a free survey with inside and outside inspection, moisture readings, diagnosis and a written quotation for recommended work.
What training should a damp proofing technician have?
Ask about training relevant to identifying moisture problems and applying the proposed system. Our technicians are PCA trained and Safeguard Ltd trained. Also ask how the inspection findings support the treatment they recommend.
Is it normal to be told I need a damp proof course straight away?
The recommendation should follow an investigation and an explanation of the evidence. Ask why rising damp is the diagnosis and how condensation or rainwater entry has been considered before agreeing to an injected course.
What should a damp proofing guarantee cover?
Check the named work, duration, issuing company and conditions in the written document. Our 20-year guarantee certificate is issued on completion of damp proof course work and payment; guarantees for other work depend on the job.
Why do damp proofing quotes vary so much?
Different recommendations can involve different wall areas, preparation, repairs and finishes. Check whether each includes plaster removal and replacement, then ask for any differences in scope to be explained before comparing the totals.