Debunking Myths About UK Homes and Humidity During Heatwaves
As the UK endures yet another heatwave, discussions around our homes’ ability to cope with soaring temperatures are everywhere. A common refrain I keep hearing is: “Our homes are designed to keep heat in.” However, this explanation doesn’t hold up under scrutiny, and understanding the true factors behind our building designs and local climate is essential to effectively addressing the challenges of extreme heat.
Challenging the “Heat Retention” Excuse
The notion that British homes are inherently built to retain heat is a misconception. Today’s reality is that many older UK houses are poorly insulated compared to homes in countries such as France, The Netherlands, Belgium, and Germany. While some new-build developments are improving and align more closely with European standards, the vast majority of the existing housing stock was constructed without adequate insulation.
Insulation is a two-way street. This means that a house designed to retain heat during winter will also be less effective at allowing heat to escape during summer. Well-insulated homes can trap heat inside, making indoor temperatures uncomfortable during heatwaves — no matter what the original intent was.
Clarifying Humidity Levels in the UK
Another popular misconception is that the UK’s climate is characterized by high humidity, which supposedly worsens our ability to cope with heat. In reality, the data tells a different story.
On the recent hot days, humidity levels across various UK cities were relatively low:
- Gloucestershire: 40%
- London: 35%
- Manchester: 45%
- Newcastle: 30%
- Edinburgh: 45%
- Cardiff: 50%
These figures indicate that humidity was not excessively high, and in many locations, it was approaching low levels. For instance, Newcastle and London experienced humidity levels that are typical of dry conditions. In some cases, our climate is as dry as certain periods of the year, contradicting the idea that humidity worsens the heat problem.
Implications for Buildings and Living Conditions
The reality is that our understanding of climate and housing design needs updating. More efficient insulation and ventilation strategies — such as passive cooling methods, external shading, and natural ventilation — can significantly improve indoor comfort during intense heat. Simply relying on the misconception that “homes are designed to keep heat in” ignores these practical solutions.
Furthermore, awareness of actual humidity levels can inform better strategies for managing indoor environments, such as dehumidification or cross-ventilation