Approved Document O: Overheating (2021 edition)

This Approved Document provides guidance on how to comply with Part O to Schedule 1 to the Building Regulations covering overheating mitigation requirements and applies to new residential buildings only. It takes effect on 15 June 2022 but does not apply to work subject to a building notice, full plans application or initial notice submitted before that date, provided the work is started on site before 15 June 2023. ADO: Overheating contains the following sections: Simplified methodDynamic thermal analysisEnsuring the overheating mitigation strategy is usableProviding informationKey termsCompliance checklistAreas at a high risk of buildings overheating The guidance in this Approved Document only relates to England.