Heat Adaptation Strategy for Commercial Buildings

The report highlights that commercial buildings are a key area of focus within the Built Environment and Business and Economy sectors. It recognises that workplaces and other non-domestic buildings are facing increasing risks from overheating and require adaptation measures to maintain occupant health, comfort, productivity, and business continuity.

Key Findings Relevant to Commercial Buildings

Passive cooling measures are the preferred first approach. The report advocates interventions such as:

• External shading (e.g. canopies, brise soleil, solar control measures)
• Natural and mechanical ventilation improvements
• Building fabric enhancements and other measures that reduce heat gain

These approaches help minimise energy consumption and reduce pressure on the electricity network during periods of peak demand.

Active cooling should be considered a complementary measure rather than the primary solution. Air conditioning may be required in certain circumstances where passive measures alone cannot achieve acceptable thermal conditions; however, it should generally form part of a wider heat-resilience strategy rather than be the first response.

Future-proofing the commercial estate is essential. The report concludes that commercial buildings must transition from being designed for London's historic climate conditions to being designed and operated for a significantly warmer future. This includes:

• Retrofitting existing buildings to improve thermal resilience
• Ensuring new developments are designed to withstand higher temperatures
• Supporting businesses in adapting their workplaces and operational practices

These measures are viewed as critical to protecting employee wellbeing, maintaining productivity, and supporting London's long-term economic resilience.

1. Engineering controls should sit above the measures that rely on human behaviour such as distancing and wearing face coverings in any “hierarchy of risk control”. Building managers should address source control before studying ventilation requirements. This approach would not necessarily lead to increasing ventilation rates.
2. This is not just about flow rates as it depends on the size of the space. 10l/s per person is the ideal, but if people are close together and for an extended period we may need more flow rate.
3. There was also very little ‘real world’ evidence to prove the effectiveness of air cleaning devices.
4. Part F of the Building Regulations, which is currently under review, could be used to beef up the IAQ measures likely to be introduced in the forthcoming Environment Bill.
5. The gap is between what we write down as a standard and how we deliver. There are buildings out there that don’t have any controlled ventilation at all.