What Is Condensation Damp and How Do You Stop It?

Condensation is responsible for the majority of damp problems in UK homes, yet it's frequently misidentified as rising or penetrating damp. Understanding it properly is the key to solving it.

What Is Condensation Damp?

When warm, moist air meets a cold surface, the air can no longer hold its moisture and it deposits as water droplets. This is condensation. In a house, this happens on cold walls, windows, and in corners.

Why It Happens

Modern homes are increasingly airtight. We seal draughts, insulate walls, and block up chimneys — all of which reduce natural ventilation. Meanwhile we generate enormous amounts of moisture through cooking, showering, and breathing. Without adequate ventilation, that moisture has nowhere to go.

Signs of Condensation Damp

• Black mould on walls, especially in corners and behind furniture
• Streaming windows, particularly in the morning
• Damp, musty smell in rooms
• Mould on clothing or other soft furnishings stored against cold walls

How to Stop Condensation

1. Improve ventilation — Open windows daily, use extractor fans, install positive input ventilation
2. Reduce moisture production — Use lids on pans, dry clothes outdoors where possible
3. Insulate cold surfaces — Cold walls and window reveals attract condensation
4. Anti-condensation coatings — Applied by a professional, these reduce surface condensation

Shadbolt Plastering offers condensation diagnosis and ventilation solutions across South London and Surrey.