What is the minimum thickness of firewalls according to building regulations?

The correct answer indicates that the minimum thickness of firewalls according to building regulations is 150 mm. This thickness is typically specified to ensure that the firewall can effectively provide the necessary resistance to fire and prevent the spread of flames between different sections of a building or between separate buildings.

Firewalls serve a critical role in the overall fire safety strategy of a structure by delineating fire compartments, which limits the potential for a fire to spread and allows for safer evacuation and firefighting efforts. The 150 mm thickness is designed to accommodate the materials and construction methods used in building firewalls, ensuring they can meet fire resistance ratings as required by national and local building codes.

This thickness is also aligned with common fire rating requirements, often expressed in terms of hours of fire resistance, which is essential for compliance with regulatory standards. Different constructions may require different thicknesses based on specific building needs, but 150 mm is generally established as the baseline in many regulations, providing an adequate balance between safety and practicality in construction.