If you’ve spotted signs of damp along your lower walls – such as bubbling paint, peeling wallpaper, or white salt deposits – you may be wondering whether your damp proof course (DPC) has failed. But here’s the thing: not all low-level damp means you need a new DPC.
In fact, many of the cases we see around Warrington are caused by bridging plaster – where plaster or skirting touches the floor and bypasses the DPC altogether.
Let’s break it down.
What Is a DPC and Why Does It Matter?
A damp proof course is a horizontal barrier, usually made of plastic, bitumen, or modern silicone injection, designed to stop moisture from rising up through the walls. It’s a vital part of any building’s defences – especially in older homes across Warrington where the original slate DPCs may have degraded or been compromised.
What Is Bridging Plaster?
Bridging happens when internal materials – usually plaster, render, or timber skirting – make contact below the level of the DPC. This allows moisture to effectively "hop over" the protection, creating the appearance of rising damp, even though the DPC itself may still be intact.
In bridging cases, there’s often no salt contamination, meaning all we need to do is carefully remove the plaster behind the skirting boards – not the full metre-high strip you’d typically need for genuine rising damp. It’s a simpler, more cost-effective fix.
How Can You Tell the Difference?
At Weather Wise Solutions Limited, we use moisture mapping and diagnostic inspection techniques to distinguish between:
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Genuine DPC failure, often accompanied by high moisture readings and salt deposits.
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Condensation, which tends to appear higher up and in colder rooms.
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Bridging plaster, usually localised and without contamination.
What If I Do Need a New DPC?
If our inspection does reveal a failed DPC, we can update it using silicone-based injection systems from PAM Ties – a trusted supplier known for quality and reliability. We’ll also remove any salt-contaminated plaster and reapply breathable systems to support long-term protection.
We’re proud members of the Damp Proofing Association and the Federation of Damp, and all our damp specialists hold CPD qualifications in Dampness in Buildings.
Do You Get a Guarantee?
Yes – when we install a new DPC, we offer insurance-backed guarantees at no extra charge. Even where bridging removal alone is sufficient, we’ll still issue a guarantee for the remedial work carried out.
Book a Free Damp Quote in Warrington
Not sure whether your property needs a new DPC or just a plaster repair?
Book a free survey with Weather Wise Solutions Limited here.
We’ll visit your home, carry out a full inspection, and give you honest, straightforward advice – with no obligation.