The sun’s started shining and I’m sure you’re hoping for a bit of spring heat over the Easter weekend. However, whilst warmer weather means we can finally turn the heating off, higher temperatures can result in overheating, especially in newer properties.
If your home was built in the last 20 years or so, it will have been designed to minimise heat loss in order to reduce energy consumption and carbon dioxide emissions. Successive iterations of Building Regulations have meant that a home built in 2019 has nearly half the carbon dioxide emissions of one built in 2002, in theory at least. This has been achieved through improvements to insulation requirements and reduced air leakage. But by making the building better at trapping heat in the winter, it also traps heat in the summer, meaning that a home built in 2019 is more likely to overheat, with apartments in urban locations at highest risk.
For a healthy adult, overheating might mean a bad night’s sleep, exhaustion or dehydration. However, for the elderly and young children, overheating can have more serious health consequences, as these groups are less able to control body temperature effectively. Indeed, it is estimated that the 2003 heatwave was responsible for 35,000 deaths across Europe. As the climate warms, weather events like this will become more frequent, and more people will be affected if the implications of overheating aren’t properly considered. Cases of residential overheating are dealt with by Environmental Health Officers serving notice under the Housing Act 2004, with dwellings often being declared unfit for habitation, leading to costly remediation works.
SAP, the Government approved software for assessing energy use in new homes, contains a rudimentary assessment of overheating risk. However, this is known to be inaccurate and lacking in detail. The Chartered Institute for Building Services (CIBSE) has published guidance on assessing overheating using more detailed methodologies, and the Mayor of London has rightly adopted these as part of the London Plan. For residential schemes that don’t fall within the remit of the Mayor or are outside London, the CIBSE guides are voluntary, and these homes are therefore more likely to overheat.
Thankfully, awareness of the issue is increasing, especially for vulnerable groups. The growing market of third age living developments, whose residents will be more susceptible to the health impacts of overheating, are now being examined more closely to ensure that overheating risks have been sufficiently mitigated.
With the government aiming to build over 300,000 homes per year by the mid-2020s, and a Building Regulations review due later this year, isn’t it time to recognise that overheating isn’t a London problem, or a big development problem, or a care home problem?
Mitigating the risks posed by overheating forms an integral part of the Sustainability work we do at Iceni Projects. We would welcome wider adoption of detailed overheating standards to ensure the health and wellbeing of all new home owners.