The Truth About "Free" Damp Surveys – Are You Being Misled?

Damp problems can be frustrating, especially when companies offer "free surveys" that seem like a convenient way to get an expert opinion. At first, these offers may sound like a great deal—after all, who wouldn’t want a professional assessment at no cost?

However, after years of experience dealing with damp issues, I have learned that these so-called “free surveys” are rarely as helpful as they seem. More often than not, they are just a sales tactic to push costly treatments that fail to address the real problem.

If you are facing damp issues, here is what you need to know before accepting a free survey.

The Catch Behind Free Damp Surveys

A free survey may not cost anything upfront, but the true cost comes later—usually in the form of expensive treatments that you may not even need.

Here is how many free surveys typically work:

• A surveyor arrives with a basic moisture meter and takes a quick reading at the lower part of the wall.
• They find some level of moisture (which is common in many homes) and immediately diagnose “rising damp.”
• They recommend chemical damp-proof injections and membrane installations—often costing thousands of pounds.
• The treatment is carried out, but the damp issue remains unresolved, leading to further problems down the line.

This pattern is something I have seen repeatedly. The reality is that rising damp is rarely the true cause of a damp issue, and chemical treatments are often ineffective.

The Myth of Rising Damp

One of the most common claims made by damp-proofing companies is that your home is suffering from rising damp. But here is the truth: rising damp is not as common as these companies want you to believe.

Most homes are built with a damp-proof course (DPC) that prevents moisture from rising up through the walls. Unless the DPC has been physically damaged or compromised, it is unlikely to fail.

Despite this, many companies diagnose rising damp simply because it allows them to sell expensive treatments. The idea of moisture magically travelling up a wall is rarely supported by real evidence—but it remains a convenient excuse to push chemical injections and membranes.

What’s Really Causing the Damp in Your Home?

Instead of assuming rising damp, it is important to look at other, more likely causes of damp problems, such as:

Condensation – A common issue in homes with poor ventilation, condensation occurs when excess moisture from cooking, showering, or drying clothes indoors is unable to escape.

Penetrating Damp – Water can enter through cracks, defective pointing, or damaged external render. Faulty roofing or guttering can also allow water to seep into walls.

Leaks – A hidden pipe leak or a problem with plumbing connections may be causing damp patches inside the home.

Bridging of the DPC – If external soil levels, internal plaster, or wall coatings cover the damp-proof course, moisture can bypass it and cause damp problems.

A professional damp assessment should investigate all possible causes rather than jumping to the conclusion of rising damp.

How to Identify a Genuine Damp Survey

A reliable damp survey should be thorough, unbiased, and focused on finding the actual cause of the problem. Based on my experience, a professional damp survey should:

• Use proper diagnostic tools such as thermal imaging cameras, rather than relying solely on a basic damp meter.
• Test multiple areas of the property, not just the lower sections of walls.
• Check for damp above 1 metre from floor level—if it is dry higher up, then it is unlikely to be rising damp.
• Provide a detailed written report with clear recommendations based on evidence.

If a surveyor is quick to recommend chemical injections without fully investigating the issue, it is a sign that they may be more interested in selling a product than solving the problem.

Why Quick Fixes Can Lead to Bigger Problems

Many homeowners who accept free surveys end up paying for treatments such as:

• Chemical damp-proof injections
• Plaster removal up to 1 metre high
• Installation of vertical damp-proof membranes

While these treatments may appear to resolve the issue in the short term, they often fail to address the underlying problem.

For example, a vertical damp-proof membrane might prevent damp from showing on the surface, but the moisture remains trapped behind it. Over time, this trapped moisture can damage brickwork, mortar, and internal structures, leading to costly repairs in the future.

Before agreeing to any damp-proofing work, ask for clear evidence that the recommended treatment is necessary.

Why Paying for a Professional Damp Survey is Worth It

Over the years, I have come to realise that paying for a proper damp survey is a far better investment than relying on a free assessment.

When you choose a professional, independent surveyor, you benefit from:

1. An unbiased diagnosis – Without a financial incentive to sell treatments, a paid survey is focused on finding the real issue.
2. Expert knowledge – A qualified surveyor with years of experience can provide reliable recommendations based on facts, not sales tactics.
3. A thorough investigation – Using advanced tools and multiple testing methods ensures an accurate diagnosis.
4. A detailed report – Instead of vague recommendations, a professional report will outline clear solutions that are tailored to your home.

A proper damp survey can save you thousands of pounds by ensuring you only pay for necessary treatments rather than ineffective quick fixes.

Final Thoughts...

If you are considering booking a free damp survey, take a moment to ask yourself:

• Has the surveyor provided evidence of the cause of the damp?
• Did they check multiple areas of the property or just focus on floor-level readings?
• Are they recommending a solution based on facts, or simply trying to sell a product?

Damp problems should be addressed by identifying and fixing the real issue, not by applying quick fixes that mask the symptoms.

From my experience, choosing an independent, professional damp survey is the best way to protect your home and your finances. If you are dealing with damp issues, make sure you are getting honest advice—not just a sales pitch.