Britain experienced its hottest June day for the third consecutive day as temperatures neared 37 degrees Celsius (98.6 degrees Fahrenheit). However, inhabitants of newly constructed homes have reported experiencing even more extreme indoor heat, with some likening their living spaces to the Sahara Desert.
New-build properties in the UK are designed with high energy efficiency, featuring robust insulation, airtight construction, and large, unshaded windows intended to maximize natural light. While beneficial for retaining warmth during colder months, these features contribute to significantly higher indoor temperatures during heatwaves. Social media users have shared their experiences, describing walls that are hot to the touch and sleeping conditions that are uncomfortably warm.
One resident, Rosie Mantalbano, described her house as feeling like it was "sponsored by the Sahara Desert" while outside temperatures reached 32 degrees Celsius. Despite opening windows early and keeping curtains closed throughout the day, she noted that the heat persisted, making even nighttime temperatures unbearable. Another TikTok user, Abigail Jade Brown, called her new-build home "hell" during the heatwave. One account, @ourcastletonhome, registered an indoor temperature of 29.5 degrees Celsius.
Stan Milsom, another new-build resident, stated that his home is often hotter inside than outside and is considering installing air conditioning to cope. He advised potential buyers to be prepared for extreme heat in such properties.
Experts suggest that traditional British homes were designed for a colder climate, with building regulations only recently beginning to address cooling in summer. Dr. Ben Roberts, a senior lecturer in healthy buildings at Loughborough University, noted that while the focus has historically been on winter warmth, new regulations since 2022 are starting to consider summer cooling, indicating a need for adaptation.
Guidance for mitigating indoor heat includes keeping blinds or reflective curtains closed during the day to prevent solar gain. For ventilation, opening windows on opposite sides of the house during the coolest parts of the day, typically overnight or in the early morning, can create better airflow. Experts caution against opening windows when the outside temperature is higher than indoors, which is often the case during peak heatwave hours.
If a home has limited ventilation, a fan can help circulate cooler air from outside. However, fans are advised to be used only when people are present, as they do not change the air temperature but rather move air, providing a cooling effect through evaporation on the skin.
The Met Office recorded a high of 36.9 degrees Celsius in Wattisham, Suffolk, marking the third consecutive day of record-breaking June temperatures. These high temperatures have prompted the UK Health Security Agency to extend amber alert heat warnings across England, advising of potential increases in mortality, particularly among vulnerable populations.