The Elmhurst Overheating Scheme has released a Part O report template in collaboration with the National House Building Council (NHBC), with the aim of refining the approval and sign off process.

The Part O report template has been produced off the back of various delays in the process since Part O came into effect in June 2022 and applies to assessments through the Dynamic Thermal Modelling route.

Feedback has suggested that a number of reports handed to building controls lacked the information needed to easily verify onsite mitigation strategies, to ensure the requirements of the Part O assessment had been met. Therefore, with this feedback, and the industry expertise of NHBC and Elmhurst combined, this overheating report has been created to tackle these issues.

The purpose of the report is to make the design features and overheating mitigation strategy clear to the report recipients, including building control bodies. The benefits of using the report correctly include a reduction in the number of queries about the modelling and design features, thereby reducing delays. This report will be available only to members of the Elmhurst Overheating Scheme and we strongly encourage all members to follow it.

Members of the Elmhurst Overheating Scheme are deemed competent at dynamic thermal modelling through training and annual competency assessments. This, alongside the report template, should ensure a smooth process.

Richard Smith, Head of Standards, Innovation & Research at NHBC, comments:

‘Using dynamic thermal modelling to assess overheating in new dwellings is undoubtedly a complex process, however TM59 provides clear reporting requirements. This enables stakeholders to understand the outcome, its basis and any design implications, all of which need to be considered in relation to the guidance in Approved Document O. The Elmhurst competency scheme should help avoid delays, as building control professionals will have confidence in the assessments provided. Additionally, when modellers use Elmhurst’s standardised reporting, key information is presented in a clear and consistent format, avoiding confusion and ensuring measures modelled are included in detailed designs. This will provide real value to the overheating assessment process.’

If you receive one of these reports, you should verify that it has been completed by a member of the Elmhurst Overheating Scheme by searching their member ID on our Find An Assessor directory.

If you wish to learn more about Overheating Risk Assessments and the Elmhurst Scheme, visit our Overheating Competency Scheme webpage.