Making retrofit cool
The need to decarbonise the UK’s building stock has catapulted refurbishment and retrofit to the top of the political agenda. BESA Technical Director Graeme Fox says we must grab this opportunity to tackle the growing overheating crisis.
Rising global temperatures have prompted the Met Office to consider naming heatwaves (just as it already does with our increasingly frequent storms) for the first time, with an influential group of government advisors warning that rising summer temperatures could soon be responsible for up to 10,000 excess UK deaths every year.
A new report from the Environmental Audit Committee (EAC), prompted by the UK breaching the 40°C mark for the first time in 2022, has warned that we are poorly prepared to deal with this ‘silent killer’ and that deaths will be highest among vulnerable groups including the elderly and the socially disadvantaged.
The ‘Heat resilience and Sustainable Cooling’ report says that both physical and mental health are affected by rising temperatures, with suicide risk believed to be twice as high when the temperature reaches 32°C compared with 22°C.
The committee of MPs also said high temperatures cost the UK economy £60bn a year owing to work-related accidents and lack of sleep. It said more than 4.6 million homes in England experience summertime overheating – underlining the huge scale of our retrofit challenge.
Complexion
This puts a whole new complexion on the debate between retrofit and rebuild on the road to net zero.
With the need to retrofit both residential and commercial buildings to improve energy efficiency already established as part of the UK’s net zero ambitions, addressing overheating must now be built into any comprehensive national retrofit programme.
Passive cooling measures, such as green roofs and solar shading, can mitigate some of the problem and would require no additional energy input, but similarly efforts to decarbonise heat and improve ventilation for health and well-being must be addressed simultaneously.
For example, improving building airtightness should not lead to additional overheating problems so long as the ventilation and cooling measures are designed alongside. In fact, the opposite is true as better building fabric with intelligent ventilation solutions makes it easier to control indoor temperatures and reduce other problems such as condensation and mould.
The EAC also recommended adding the use of ceiling fans to the building regulations, which is an example of how we could embed anti-overheating measures into existing mechanisms for incentivising quality improvements in both retrofit and new build.
However, delivering such solutions at the necessary scale will require a huge recruitment drive to address skills shortages. The EAC also reported a potential shortfall of 250,000 people in suitable roles by 2030, which it called the “net-zero tradespeople crisis”.
All of this puts the current furore over the Labour party’s decision to drop its plans for a £28bn ‘green prosperity plan’ into context. While this decision betrays the current confused state of political thinking around net zero, it also reveals a deep-rooted misunderstanding of the scale and nature of this opportunity.
Contrast that Labour ‘ambition’ with the $2trillion a year in savings that global businesses could make from implementing easy to achieve energy efficiency measures, according to the World Economic Forum (WEF) and the financial consultant PwC.
Its report ‘Transforming Energy Demand’ was backed by more than 120 CEOs of large global corporations and concluded that retrofitting buildings alone could cut global energy demand by 12%.
It concluded that buildings were responsible for 30% of the world’s energy usage in 2022 but that they also offer the greatest energy reduction potential of all economic sectors. WEF researchers calculated that energy intensity in buildings could be reduced by 38% using existing solutions.
The WEF also emphasised retrofit’s wider benefits including reduced staff absenteeism and improved productivity (because retrofitted facilities are higher quality) and the creation of 3.2 million jobs worldwide to deliver retrofit programmes.
The WEF researchers concluded that energy efficiency was the most “under-addressed” aspect of global approaches to net zero. It claimed proven measures could deliver a short-term, cost-efficient reduction in energy demand of almost a third shared across the buildings, industry, and transport sectors.
Dividend
Even more significantly, it also estimated that retrofitting buildings can increase their value by up to 15% as they command higher rental or sales prices. Better buildings more than pay for themselves and society gets the wider health, wellbeing and quality of life dividend of a better adapted and more resilient built environment.
With the business community zeroing in on the reputational benefits of net zero alongside the very real efficiency improvements and cash savings, this gives our industry a fantastic opportunity to seize the agenda and drive both net zero and overheating work forward.
The Future Homes and Buildings Standards, which are due to come into force next year, could also play a big role by embedding the ‘whole building’ approach where better standards encompass fabric improvements, low carbon heating and both natural and mechanical ventilation with heat recovery solutions.
The surge in heat pump demand shows how financial incentive and legislation can work together to make progress, but individual technologies can only achieve so much. In fact, heat pumps are a good example of a solution that can only achieve its full potential as part of a wider whole building retrofit.
The Standards will also stress the key role to be played by heat networks in coming years as we seek to move from whole building to whole community decarbonisation solutions.
The UK Green Building Council (UKGBC) has also highlighted the importance of retrofit for large office buildings to capture some of the ‘easy wins’ also identified by the WEF report through modest investment in low-cost, low-disruption measures.
It has issued a wake-up call for commercial building owners who are staring down the ‘stranded asset’ barrel due to the tightening of minimum energy efficiency standards (MEES), which it estimates could leave 77% of UK office stock unlettable by 2030 because they fail to achieve the minimum energy performance certificate (EPC) rating of B.
The UKGBC report concludes that “deep retrofitting” can cut operational energy use by as much as 65%, but that this could be achieved through a light touch step-by-step approach to minimise disruption and avoid the need for full-scale, intensive programmes.
However, it believes this should be supported with mandatory reporting of whole life carbon for major projects to allow a meaningful comparison between retrofitting and rebuilding so that the most effective (including cost-effective) solution can be selected for each building.
Money talks and that will be key to getting investors on board. But so does social need. Poor quality buildings are already contributing to an epidemic of poor respiratory health and placing a huge burden on the NHS.
With overheating set to worsen as summer heatwaves become ever more regular, the clamour for holistic retrofit programmes will only intensify and make ever more obvious economic and social sense.
