New dwellings and new residential buildings must comply with the Building Regulations Part O

Has your project failed Part O Simplified Method?

Then you must use Dynamic Thermal Modelling.

DTM Part O specialises in this methodology.

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Part O requires that new dwellings and new residential buildings, such as student accommodations, care homes, and prisons, comply with CIBSE TM59 dynamic thermal standards. 

Part O of the Building Regulations do not apply to non-residential buildings and buildings undergoing a change of use.

CIBSE TM59:2017 (Design Methodology for the Assessment of Overheating Risk in Homes) establishes an industry-standard approach for predicting overheating risk in residential buildings using dynamic thermal simulation.

Thermal Dynamic Modelling for Overheating Assessment Part O and TM59 Compliance

As global temperatures rise and modern buildings feature larger glazing and high-performance materials, overheating is becoming a significant concern in UK homes and buildings. The newly implemented Building Regulations Approved Document O (Part O), effective from 15 June 2022 in England, provides guidelines on the legal and technical requirements for new residential buildings to meet overheating standards.

Part O of the Building Regulations specifies two methods for achieving overheating compliance:

  1. The Simplified Method: This method sets maximum allowable glazing areas and minimum free areas of openings in rooms and buildings to limit solar gains and remove excess heat.

  2. The Dynamic Thermal Modelling Method: Compliant with CIBSE TM59, this method offers greater design flexibility and a more precise analysis of overheating risks. Dynamic thermal modelling employs advanced computer software to predict overheating possibilities. It considers a wide range of design and occupancy parameters, analysing them at short time intervals to provide a more accurate reflection of a building's performance.

DTM Part O use the industry-leading software, IES VE dynamic simulation software, to construct precise 3D models of your building and assess overheating risks effectively.