Changes to the management of the Building Safety Regulator has created an opportunity to address what is often referred to as the most overlooked building safety issue – lack of ventilation and cooling, writes BESA’s director of specialist knowledge Rachel Davidson.
The UK is becoming accustomed to increasingly frequent and more intense summer heatwaves, but our existing building stock can’t cope. Most British homes overheat every summer, but the country still has a difficult relationship with air conditioning/mechanical cooling, which has long been regarded as something of a luxury.
Instead, we continue to focus on improving insulation to reduce heat loss driven by Net Zero targets and this has, in many cases, been at the expense of adequate ventilation. So, the same buildings that can’t be effectively cooled in summer also suffer from damp and mould in winter.
It has led to a dramatic rise in respiratory problems, particularly among children, the elderly and those suffering from underlying health problems. Addressing this issue is, therefore, not just about cooling or heating spaces but also controlling humidity and indoor air quality (IAQ) to protect the most vulnerable in our society.
During the Covid-19 pandemic, members of the government’s Scientific Advisory Group for Emergencies (SAGE) suggested lack of proper ventilation was “the most overlooked building safety issue”.
Productivity
Numerous studies have also shown how elevated temperatures – even those well below what the UK has been experiencing this month – negatively affect the human body. For example, research by the US space agency NASA found that productivity fell by 3.6% for every 1degC the indoor temperature rose above 22degC.
The British Council for Offices (BCO) says temperatures in commercial buildings should be maintained at between 20 and 24degC. It also recommends ventilation rates of 12 litres per second per person (l/s pp) of filtered air with an additional 10% in high density occupied spaces to protect the health, well-being, and productivity of occupants.
The BCO also says that controlling humidity is crucial, but its most recent studies showed the average relative humidity (RH) in offices was 38% whereas for good health it should be between 40 and 60%. At 35% people will experience eye irritation, nasal dryness, and sore throats.
BESA members have been sounding the alarm bells about overheating in buildings and the associated health risks for years, but the news that the government is considering grants of £7,500 per household to install air-to-air heat pumps that providing both heating and cooling as part of proposed changes to the Boiler Upgrade Scheme suggests alarm bells may now be ringing in Westminster too.
The recently announced revamp of the Building Safety Regulator (BSR) is another opportunity to address this full-blown building health and safety concern.
Last month, the Ministry of Housing, Communities, and Local Government (MHCLG) put enforcement of the Building Safety Act 2022 in the hands of a new board led by two senior fire officers to try and unblock the planning system.
While this reflected the regime’s primary focus on fire safety, initial conversations with the new team confirmed that they will not attempt to turn buildings into fire safe ‘fortresses’ at the expense of other considerations but are determined to address all aspects of health, safety and well-being.
This followed the publication of a BSR case study which explained why up to 70% of all designs were being rejected at planning Gateway 2. Most lacked “basic information” including fundamental details about fire safety and structural elements of higher risk buildings.
As well as addressing these failings, the renewed focus on the quality of planning submissions is a great opportunity to ensure all life safety measures are properly detailed including those needed to address overheating, condensation and poor IAQ.
As an industry, we have a responsibility to improve the quality of our submissions – and by doing so the Regulator and the mechanical, electrical and plumbing (MEP) industry can develop this new planning system together.
Last resort
In fact, it should not be that hard. The standards required are already there in the Building Regulations, and the BSR has often repeated that it only needs to see evidence that submissions are meeting these existing standards. For example, Part O (for overheating) of the building regulations allows for the use of mechanical cooling/air conditioning, but only as a ‘last resort’ once all passive/lower energy routes have been exhausted.
It focuses, first, on limiting solar gains in summer through shading and addressing the solar heat gain coefficient of glazing. It also requires measures for removing excess heat, firstly via natural ventilation through opening windows and ventilation louvres but does acknowledge that this may not be sufficient or many of the UK’s existing buildings.
Purge ventilation is another suggested approach to help the design comply with Part F (for ventilation), but it also acknowledges that factors like noise, pollution, and security concerns could have an impact on the success or otherwise of this approach, and the current heatwave season has once again highlighted how difficult it is to cool and ventilate these spaces passively.
The bias against mechanical cooling was reinforced by the energy/low carbon goals enshrined in Part L of the regulations, which then took precedence among the building design community as it worked towards Net Zero. It must now be acknowledged that the rapid development of more sophisticated heat pump technology means the UK population has access to solutions that can deliver healthier buildings at minimal energy penalty.
Planning applications will improve if we respond positively to these requirements and ensure full details are provided at each stage. Arguments for and against mechanical cooling to address overheating can, therefore, be framed as part of a fully rounded planning application.
Many of these issues will also be teased out in the findings from BESA’s second annual in-depth survey that sets out to discover why companies are struggling to adapt to the new building safety regime.
The research, which is being carried out in partnership with the construction analysts Barbour ABI, should therefore be able to support the new fast track planning process being developed by the new BSR team.
It is aimed at companies of all sizes from right across the building engineering spectrum to assess levels of awareness and understanding of legal responsibilities and the implications for individual competence and organisational capability. The findings will be published soon and will help us shape future training and guidance.
There has been plenty of soul-searching and much recriminatory talk about who is to blame for the slow progress of the building safety regime, but that is now in the past. We have a way forward through the new BSR approach that promises not just safer but healthier buildings too.
Poorly ventilated buildings make us ill, overly hot buildings make us slow and unproductive (as the NASA study proved), but we have a wide range of low energy, mechanical solutions that can be deployed at scale into new and, importantly, existing buildings.
Find more information about the Building Safety Act and BESA’s resources here.