Why Moisture Readings Matter: How Our Level 3 Home Survey Prevented a Costly Floor Collapse

At Bramble & Wagg, we often hear sellers and agents say, “Don’t worry, the damp’s been dealt with.”

But has it really?

On a recent Level 3 (Building) Survey in Nottingham, we inspected a beautiful Victorian home that had undergone damp treatment in the past. The work appeared sound from above ground — new plaster, fresh paint, and no major odours. But what we uncovered in the cellar told a different story.

Using a Protimeter moisture meter, we took readings from the exposed timber floor joists. Despite the apparent remedial work, the timber still showed readings exceeding 20% moisture content — classed as “wet” and within the danger zone for fungal decay. Worse still, these were not original joists. They had been replaced approximately 25 years ago after the original timber had failed.

Today, they were already beginning to deteriorate.

What Does a Protimeter Reading Actually Mean?

Protimeter moisture meters are widely used by surveyors and damp specialists, but readings alone don’t provide the full picture. Our role is to interpret these results in the context of the property.

• Readings up to 15% = Air dry, safe
• 15% to 20% = Risk zone, needs monitoring
• 20%+ = Wet, decay likely or already underway

In this property, repeated high readings across multiple joists raised an immediate red flag. Our visual inspection confirmed signs of rot and erosion at the ends of the joists where they met the supporting walls — classic signs of ongoing damp problems.

Why Was This Missed Before?

In many property transactions, the condition of the subfloor goes unchecked. A buyer might rely on the seller’s word or assume that visible finishes reflect structural soundness. But unless someone enters the cellar or lifts floorboards, early warning signs can go unnoticed.

Even if a contractor or builder has previously carried out damp treatment, this doesn’t guarantee the issue has been resolved at its source. In this case, the damp proofing appeared to have addressed wall finishes, but inadequate ventilation and historic moisture ingress were still affecting the structure.

How Our Survey Helped

Because we provided a Level 3 survey — the most comprehensive RICS Home Survey available — we were able to:

• Access and inspect the cellar area
• Identify defective timber and elevated moisture
• Provide photographic evidence and detailed recommendations
• Flag the absence of adequate cross-ventilation
• Alert our client to the need for timber specialist input

We also conducted a follow-up MS Teams call with the client to explain our findings in plain English. This allowed them to return to their solicitor and ensure the seller provided further information, or to adjust their offer accordingly.

Why This Matters to You

Structural timber decay is not only expensive to remedy — it can also be dangerous. Floor joists affected by wet rot or dry rot can lose strength and lead to sudden collapse, especially under load.

Without a professional survey, the buyer could have moved in unaware of the issue. Repairing this type of defect would likely involve lifting floors, replacing joists, and undertaking damp remediation work. That’s major disruption in the early months of ownership.

By investing in a proper pre-purchase survey, the client saved themselves thousands in unforeseen costs and potentially weeks of stress.

Why a Surveyor Still Matters (Even If You Have a Builder)

We sometimes hear, “We’re taking a builder round instead.”

While builders play an important role, a Chartered Surveyor brings:

• Professional training in building pathology
• Independence from the transaction
• A holistic view of risk, condition and compliance
• Clear reporting suitable for lenders, insurers, and solicitors

In short, we don’t just tell you what needs fixing. We tell you what it means, how urgent it is, and what steps you can take.

Serving Nottingham and the East Midlands

We conduct residential surveys across Nottingham, West Bridgford, Mapperley Park, Derbyshire and Leicestershire. Our reports combine modern tech, clear recommendations, and the human touch.

Need a Homebuyer Survey or Level 3 Building Survey? Let’s make sure your dream home doesn’t come with nightmare repairs – Book a Survey Today!