Find out how the new AD L will impact your upcoming developments AD L White Paper
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Overheating Risk

A new volume of Building Regulations has been published that will ensure all newly built homes are comfortable to live in and designed to reduce the risk of overheating in summer months. It’s a hot topic that needed addressing for some time.

How Energist can help

The Approved Document for Overheating (AD O) will go live on all new sites in England from June 15th, 2022. A similar document is expected to be launched in Wales shortly.

The design of all new dwellings will need to be checked to make sure there are enough openings to allow for good air flow in summer months, while also checking the amount of windows isn’t excessive to cause high levels of solar gains, as that can lead to uncomfortably hot living conditions.

Targets are stricter for sites built in the centre of our two biggest cities – London and Manchester, and will put particular pressures on designers of heavily glazed blocks of flats, or where dwellings don’t have openable windows on opposing walls.

In these cases, enhanced 3D thermal dynamic modelling will be required to confirm the design is not at risk of overheating.

Developers who wish to avoid such detailed modelling may choose to reduce window sizes, include solar shading or even install external shutters as alternative routes to keeping buildings cool.

Energist’s Technical Team will soon be able to check your current building designs against the proposed new overheating requirements to confirm, with certainty, how they will perform against the new targets.

Request a quote Meet the team

Mark Asimakis

Energy Planning Manager


Mark Asimakis

Energy Planning Manager

Why choose Energist?

  • Overheating is not a new discipline for us. Our London Planning team has years of experience producing bespoke 3D modelling and running models in line with the TM59 standard.
  • If the dynamic method sounds a like too big a step initially, we are also providing advice on how to comply with the Simplified Method.
  • We can guide you through the new requirements for AD O in England, and are poised to offer the same level of service in Wales once these separate requirements are confirmed.

Complete solutions from Energist

  • The introduction of an overheating target into Building Regulations is part of a major wave of change in 2022 which will re-shape how we construct our homes and places of work in the UK.
  • The Future Homes Standard policy also includes substantial rewrites to Approved Document L, which will change SAP and SBEM calculations, and also Approved Document F which covers air permeability, ventilation systems and air quality.
  • When Part L was last updated seven years ago, Energist’s Technical Team was proactive in promoting the changes, and offering workshops and seminars to help architects, designers and builders understand the new rules. We’ll be repeating our successes through 2022.