Improvements in the energy efficiency standards for both new and refurbished homes means that dwellings are now better insulated and more airtight than ever. However, a regulatory focus exclusively on the prevention of heat losses in winter has failed to address the growing numbers of homes overheating in summer, particularly in towns and cities where ambient temperatures can be significantly higher.

Approved Document O (Overheating) provides guidance on how to comply with the new requirements. Alongside the prevention of overheating in domestic dwellings, the new Part O also applies to overheating in properties, such as care homes and student accommodation.