Research and analysis

Fire safety: Open-sided car parks

Research into evidence on the fire resistance ratings for open-sided car parks, examining fire spread, structural failure risk and protection measures.

• From: Health and Safety Executive
• Published: 22 December 2025

Applies to England

Documents

Real fires: Open-sided car park fire resistance (introduction and conclusion)

HTML

Real fires: Open-sided car park fire resistance (full report)

PDF, 12.4 MB, 320 pages

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Details

The research examined the fire resistance ratings needed for open-sided multi-storey car parks and the level of safety they provide. 

Researchers analysed how fires start and spread in car parks, including how vehicle fires and car-park design features influence the rate of fire growth and overall fire propagation. 

The study considered factors such as: 

• how quickly fires spread between vehicles 
• the impact of layout, air flow and openness on fire development 
• typical occupant loads and how many people may be at risk 
• the likelihood of structural elements failing under different fire-resistance and protection options  

A lifetime cost analysis compared different fire-resistance and protection options to identify which provide the best balance of safety and cost.

Background

The government commissioned the research as part of the investigation of real fires project. 

OFR Consultants carried out the work, and the findings and recommendations do not represent government policy.

Published 22 December 2025