More than 1.3 million households in England are living with damp, according to a new report by Airflow. The figure marks a relative 25% increase over the past decade, reversing a period of decline between 2013 and 2019.

Ventilation emerges as one of the strongest predictors of damp in a home. Just under 236,000 (1%) English dwellings have been found to have inadequate ventilation. Of these, 60% had damp problems, compared with only 5% of homes with adequate ventilation.

The UK’s Invisible Air Quality Problem report comes as Awaab’s Law enters effect from October 2025, requiring social landlords to address damp and mould within strict timeframes or face unlimited fines, putting increased pressure on landlords and developers to improve housing standards.

Around 12% (three million) of homes report having an external element in poor condition (chimneys, roofs, walls, windows, doors), rising to 14% of private rented dwellings. Around 15% (453,000) of these homes also have damp.

Damp is present in 19% of dwellings with internal disrepair. Homes with heating systems in disrepair were over twice as likely to have damp (23%) as those with only kitchens/ bathrooms in disrepair (10%).

Houses were more likely to have damp present in bathrooms, bedrooms and living rooms (2.1-2.3%) than in kitchens (1.6%) and circulation spaces (0.9%), owing to the increased humidity and reduced air circulation.

The data reveals nearly half of households with damp (47%) contain someone with a long-term health condition, compared with 33% in 2013. More than one million children and 324,000 people over 65 are currently living in damp homes, groups identified as most vulnerable to the effects of poor indoor air quality.

The findings also highlight the financial burden of living in a home with damp. Households affected spend on average £270 more per year on energy bills than those without damp (£1,918 vs £1,648). Homes with the lowest energy efficiency ratings (E–G) are also four times more likely to have damp than the most efficient homes (A–C).

Alan Siggins, managing director of Airflow said: “These findings show that damp is not only a maintenance issue, but a wider public health and social challenge.

“Poor ventilation and damp housing contribute to illness, higher household maintenance costs and affected wellbeing. Tackling this requires a greater focus on ventilation standards and long-term investment in housing quality.

“With proper planning and commitment to meeting regulatory requirements and better ventilation design, housing developers can both protect tenants from damp-related health issues while creating a more sustainable and future-proof housing stock.”