How to Spot (and Fix) Hidden Damp Before Winter Hits

Damp is one of the most common — and most misunderstood — issues in student housing. As winter sets in, landlords should be proactive in spotting, preventing and educating tenants about damp before it becomes a serious (and costly) problem.

Here’s how to deal with it properly.

1. What Causes Damp in Student HMOs?

Most landlords think of damp as a leak issue — but in reality, it’s often caused by condensation, not structural problems. Especially in student properties, where:

• Large groups create more moisture from cooking, washing, and breathing
• Clothes are dried indoors on radiators without proper ventilation
• Shower steam and wet towels aren’t aired out
• Windows stay shut for heat retention, especially in winter

The result? Moist air condenses on cold external walls — particularly in corners, behind beds, and wardrobes. That’s where mould forms first.

Telltale signs:

1. Mould patches on external walls, not ceilings
2. Condensation on windows in the morning
3. Musty smells in wardrobes or corners
4. Black spots behind furniture

2. How to Fix It — The Right Way

You can’t fix damp with bleach alone. The key is reducing airborne moisture and improving ventilation:

• Encourage tenants to open windows regularly, even in winter — 10 minutes a day can make a big difference
• Provide dehumidifiers — they help dry out the air and prevent mould build-up
• Check extractor fans in kitchens and bathrooms are working (and actually being used)
• Move furniture slightly away from external walls to allow airflow
• Use mould-resistant paint on walls prone to condensation

Bonus: dehumidifiers don’t just prevent mould — they also make the property more efficient to heat, because dry air warms faster. They also give off a small amount of heat as they run as the air dries.

3. Pro Tips for Prevention

Damp prevention isn’t just about the property — it’s about tenant education too.

• Include a “moisture management” guide in your welcome pack or tenancy agreement
• Explain why condensation happens and how to reduce it
• Add a clause requiring tenants to use extractor fans and open windows periodically
• Provide clear instructions for dehumidifier use
• Inspect problem zones mid-tenancy (e.g. winter checks)

And of course, check for the obvious too:

1. Leaking guttering or roofing
2. Rising damp at ground level
3. Blocked air bricks or vents

Final Word

Damp isn’t always a maintenance failure — but if you ignore it, it will become one. Most student properties are at risk simply because of how they’re used.

Don’t wait for mould to appear — educate, ventilate, and dehumidify. Prevention is cheaper than plasterboard.