How to spot damp and mould in a commercial property

Damp and mould aren't just a residential problem. Commercial properties, offices, retail units, warehouses and leisure facilities are just as susceptible, but the consequences of leaving it untreated can be significant: structural damage, health risks to staff and customers, and costly repairs down the line.

The good news is that damp is usually detectable early if you know what to look for. Here's a practical guide to spotting the warning signs in a commercial property.

1. Visible mould growth - The most obvious sign. Mould typically appears as dark grey, green or black patches on walls, ceilings or around window frames. In commercial properties it's often found in poorly ventilated areas, stairwells, storage rooms, basement spaces and behind furniture pushed against external walls. Even small patches of mould should be taken seriously. What's visible on the surface is rarely the full extent of the problem.

2. Damp or musty smell - A persistent musty or earthy smell, particularly in rooms that are enclosed or infrequently used, is a strong indicator of damp, even when there's no visible mould. This smell is produced by microbial volatile organic compounds (mVOCs) released by mould spores. If staff or visitors regularly comment on the smell, or if it's noticeable first thing in the morning before the space has been ventilated, get a professional assessment.

3. Staining or tide marks on walls - Yellow, brown or orange staining on walls and ceilings particularly in patches or lines, often indicates water ingress or damp. These marks are left by minerals and salts and they tend to reappear even after repainting if the underlying issue isn't addressed.

4. Peeling paint or wallpaper - Paint or wallpaper that bubbles, blisters or peels away from the wall is a sign of moisture trapped beneath the surface. In commercial spaces this is often dismissed as old decoration, but it's worth investigating further, especially on external-facing walls.

5. Condensation on windows and cold surfaces - Persistent condensation on windows, particularly in the morning, suggests high humidity levels in the space. Left unchecked, this creates the conditions for mould to develop on nearby walls and surfaces. Poor ventilation is usually the cause, common in retail units, kitchens and gym spaces.

6. Damp or soft patches on walls - Running your hand along a wall that feels cold, soft or slightly spongy to the touch is a sign of moisture within the plaster or blockwork. Skirting boards that feel soft or show signs of swelling are also a red flag.

When to call a professional

If you notice any of the above signs in your commercial property, the next step is a professional damp assessment. Trying to treat visible mould without identifying the source is a short-term fix that rarely lasts and can mask a problem that's getting worse underneath.

EHG Property carry out damp and mould assessments and remediation for commercial properties in York, Leeds, Wetherby, Harrogate and across Yorkshire. We identify the root cause, treat the problem properly, carry out any associated repairs and redecoration and can provide ongoing management and monitoring of problem areas.

Contact us: 01937 326007 or contact@ehgproperty.co.uk.