Computational Fluid Dynamics (CFD) modelling
Our expert CFD Modelling team works with you to understand how fire, heat and smoke behave, helping architects and design teams optimise fire strategies, demonstrate compliance and create safer buildings for our communities.
How we support your project with CFD modelling
We work closely with architects and design teams to apply CFD modelling in a way that supports the overall vision, rather than constraining it. Our role is to provide clear, evidence-based analysis that helps resolve uncertainty and move the design forward.
BB7 combines CFD modelling with fire engineering judgement, helping project teams interpret model outputs and translate them into practical fire strategy recommendations.
CFD modelling often comes into its own when a design moves beyond prescriptive guidance and a more detailed understanding of fire behaviour is needed. In these situations, we use it to help demonstrate compliance with Approved Document B, BS 7974, the ASET/RSET methodology of PD 7974-6, BS 9991 and BS 9999.
We use CFD modelling to:
• Validate smoke control and ventilation strategies
• Support alternative approaches where standard guidance cannot be directly followed
• Assess conditions affecting occupant safety, including temperature, visibility and smoke spread
• Inform system layouts and performance requirements
In more complex scenarios, we use CFD modelling to support ASET/RSET analysis, helping to show how long conditions remain tenable before smoke and heat begin to impact occupant safety. This is particularly relevant in buildings with large occupant numbers, such as stadiums, transport hubs and commercial developments.
Where needed, we can combine this with evacuation modelling to understand how people are likely to move through the building. By looking at both fire behaviour and occupant response together, we’re able to build a complete picture and help shape a more robust fire strategy.
CFD modelling is typically undertaken during RIBA Stages 3–4, once the design is sufficiently developed. That said, we often find that getting involved earlier can be really beneficial, helping to identify potential issues before layouts are fixed and reducing the likelihood of redesign later in the project.
Research, development and innovation
Our CFD capability is supported by our Innovation Lab, where we focus on research, development and innovation to continually advance how fire engineering is applied in practice. This includes developing and testing modelling approaches, as well as working with academic partners on research into areas such as evacuation behaviour, including our collaboration with the University of Leeds.
We regularly share our insights through international conferences and published whitepapers, and bring this knowledge back into the business through ongoing training and collaboration. This helps ensure our teams are working with up-to-date thinking and a consistent level of technical understanding across projects.
By combining practical project delivery with ongoing research, we ensure our approach to CFD modelling remains relevant, robust and aligned with both industry guidance and real-world building performance.
Who we’ve helped
We bring our technical expertise and collaborative approach to validate fire safety systems and build safer communities for everyone. Explore some of our work here.
Tell us about your CFD modelling needs
If your project involves complex layouts, large occupant numbers or non-standard fire strategies, our CFD modelling can support the next stage of your design.