Part O Overheating Assessments

Building Regulations Part O is designed to prevent excessive indoor temperatures in residential buildings, ensuring occupant comfort and safety. Compliance can be demonstrated using either the Simplified Method or Dynamic Simulation Modelling (DSM).

The Simplified Method uses a set of fixed criteria based on glazing areas, window opening sizes, shading, and cross-ventilation. If a design meets these limits, it passes.

Dynamic Simulation Modelling (DSM) is a thermal analysis that models a building’s response to real-world conditions, including solar gains, ventilation rates, occupancy patterns, and external weather data. This method allows for greater design flexibility and can demonstrate compliance even when the Simplified Method fails.