Warning over overheating risk from energy efficient homes drive

Effective assessment of the risks of excessive indoor heat during summer months as a result of domestic insulation will be an important consideration for the UK’s climate change response, a new study has concluded.

Calls to ensure better understanding of the potential for overheating in UK homes, particularly properties that have been made more energy efficient has been raised in a review of a decade’s worth of research into the links between heat, energy efficiency, smart technology and health.

The review, which was commissioned by the Department for Business, Energy and Industrial Strategy, said that sufficient evidence gaps had been found around the health impacts of excess heat and the impacts of failing to ensure multiple building technologies are operating effectively.

Although the evidence used for the study was focused around the health impacts of poor heating, “excess heat” was highlighted as a problem that could be increasingly relevant in light of an increase in average temperatures due to climate change.  This in turn could have major implications for the role of cooling systems and building design.

The findings stated, “This study has shown that some energy efficiency improvements may contribute to problems of excess indoor heat in summer because greater insulation prevents heat from escaping. These risks should also be carefully assessed.”

Knowledge gaps

A particular concern identified by the study were gaps in knowledge and research into a number of areas such as the impact of excess indoor heat on health as average temperatures are predicted to rise nationally.

This concern ties into fears about how ambitions for greener heat and more energy efficient homes could create a raft of unintended negative consequences for the health and wellbeing of residents if systems are not properly planned or fail to function correctly in a building.

Researchers said that existing evidence remains unclear at present about an increase in heat-related health conditions and how they are impacted by higher indoor temperatures.

The 2014 ‘Heatwave Plan for England’ document was among the evidence reviewed for the study. It identified a risk of a number of respiratory and cardiovascular conditions as a result of excess heat.

Certain homes were identified as being at a much greater risk of experiencing excess indoor heat as a result of higher outdoor temperatures than others, according the plan.

It said, “Risk factors include being on the top floor, particularly a top-floor flat facing south or south-west, and being in lightweight buildings, in which the insulation is often on the outside of the building, which can lead to overheating.”

The plan also warned of a broad range of individuals most at risk of developing conditions from overheating homes that included people over 75, people living alone or isolated, and those living in properties within urban areas.

A lack of evidence about the links between increased levels of indoor heat and specific negative health conditions was highlighted in the heatwave plan as needing to be addressed to better understand building design issues.

The Committee on Climate Change (CCC) last month called for the issue of overheating in UK homes and buildings to be considered in a planned Climate Change Risk Assessment.

An assessment of UK climate risks and the possible opportunities to address them is set to launch next July and will be overseen by the Adaptation Committee of the CCC.  It will be the third such assessment of its kind with the previous 2017 study published in 2016.