Fire Safety Lessons from Late-Stage Design: What Goes Wrong When Safety Comes Too Late

The risks of not considering fire safety in early design stages include project delays, increased costs, and having to compromise on design features to become compliant. When fire safety considerations are integrated early, from concept stage and onwards, these risks can be mitigated, and potential hurdles can be avoided.

In this article, Richard White, Commercial Director from the UK’s leading smoke ventilation manufacturer, Sertus, explores some of the main reasons why you should take fire safety planning seriously in early-stage design. 

Bringing fire safety in early to design programmes

It’s no secret that fire safety is vital, and being compliant to regulations is a must for all construction projects. It is never going to be the most exciting aspect of any design project, which can lead to fire safety essentially being treated as just a tick-box exercise among many other tasks that designers and developers are managing. 

The problem, then, is that retrofitting safety measures can throw plans off course and increase costs dramatically. If it’s only at the “tick-box” stage that fire safety is considered, chances of delays and challenge increase significantly.

The Building Safety Act 2022 brought fire safety to the forefront of building designers minds, with the concept of ‘Gateways’ for high-risk buildings:

• Gateway 1 (Planning Stage): This requires developers to submit a fire statement to the Health & Safety Executive (HSE) at the planning permission stage

• Gateway 2 (Pre-construction): Building work is not permitted to begin util the Building Safety Regulator has approved the design. 

• Gateway 3 (Completion): All “golden thread” information (digital records of how the building was built) must be handed over before residents move in.

These three gateways mitigate the risk of high-risk buildings being built without robust fire safety solutions put in place from the planning stage. 

Typical late-stage fire safety issues

The types of fire safety issues that often get left too late in design projects include:

Compartmentation

Ensuring that construction projects are designed with passive fire prevention strategies, that limit the spread of fire and smoke. These involve barriers such as compartment walls, smoke control dampers and fire doors, as well as clear plans for cavity barriers that reduce the risk of fire spreading in between walls. 

If a design has not taken fire prevention into account, for example with large open plan areas and no preventative barriers and inadequate smoke ventilation in place, it will be non-compliant with safety regulations. Discovering this at a late stage could cause substantial problems, and result in the design compromises and additional cost to rectify the issue. 

If, however, it is considered in the concept phase, compartmentation can be included in the design process from the start.

Materials

The use of unsafe materials in construction should really no longer be an issue, in twenty-first century projects. Where fire safety is not considered throughout the design process, there is a chance that the combination of materials proposed could cause a fire risk. Identifying this early and finding compliant alternatives will be much cheaper than addressing it at a late stage, especially, of course, if materials are already installed and in use by the time the issue is identified. 

Means of escape

Ensuring that your protected routes and means of escape are fully compliant will always be important. When these have not been clearly planned from the concept phase, adding them at a later date can fundamentally change layouts and designs. 

While not a fire design failure, the Manchester Arena Inquiry highlights how late-stage and operational changes can undermine safety strategies in ways directly comparable to fire safety management failures. The inquiry found that there were issues with means of escape and crowd movement/emergency planning, which led to late-stage design changes. 

MEP Conflicts 

Mechanical, engineering and plumbing aspects in a building need to be planned in line with fire prevention and fire safety measures. For example, ensuring that sprinkler systems are not obstructed, or that pipes and conduits don’t block access to smoke control dampers and smoke vents. 

Involving fire safety at the earliest planning stage, ensures that these factors are taken into consideration throughout the process, rather than only assessed once the construction is well underway. 

Structural Changes

It’s common to see structural changes required later on in the project as a result of improper co-ordination of fire safety requirements. When changes to the building’s structure are required, this can be timely and cause significant delays to the completion of the project. 

To avoid this, it’s essential that critical fire safety design decisions are made earlier in the project, and plans are followed through at the build stage.  

How Late-Stage Design Changes Can Have Real-World Consequences

The last thing anyone involved in a construction project wants to deal with is a costly delay. But that is exactly what is at risk when fire safety is brought into the process at a late stage. 

The worst consequence, of course, would be an unsafe building, where there is risk to life from fire. With fire safety compliance a clear priority before a project is signed off, the costs of rectifying non-compliance can be substantial. 

Taking an example from the list of typical issues above, imagine a scenario in which escape routes are not adequate. Depending on when the issue is identified, the knock-on effect to all other aspects of the design could mount into problems that cost a lot not only to redesign, but especially to rework if construction is already underway.

According to the latest figures on fire safety audits from GOV.UK, 42% of the premises audited in 2024/25 were deemed ‘unsatisfactory’. This further highlights just how important it is for new buildings to consider fire safety from the design stage, with fire auditors increasingly scrutinising buildings following the Grenfell disaster and implementation of the Building Safety Act 2022 and Fire Safety Act 2021.  

Equally, imagine an open-plan design that does not meet compartmentation requirements. As well as cost, there will end up being design compromises that materially alter what the architect and designers has set out to achieve. The costs of rework and significant delays to completion dates go alongside the risk of compromises that alter the final design in ways that stakeholders are not happy with. 

Decision points after which fire safety options become severely limited

The stages of the design process when fire safety options become limited and cause risks to completion include:

• The finalisation of architectural layout, when floorplans, escape routes and staircase locations are decided

• Structural design and material selection, when structural materials are chosen and compartmentation strategies should be settled upon 

Beyond these, once construction has actually started, any changes that are required in order to become fire safety compliant will immediately incur costs of rework, and costs of delays. Whether it is start of construction, the erection of primary structure and envelope, first fix services installation, or at fit-out and finishing stages, anyone involved in the construction process will know how disruptive and expensive having to amend plans and rework building construction will be.

Best-practice approach: integrating fire safety from concept stage

All of these challenges and risks can be mitigated when fire safety is included in the project from the concept stage. 

Safety cannot be retrofitted without compromise and cost, so it’s well worth engaging with safety requirements from those very first project stages, right from when an idea for how a space will be used is being discussed.  

Stakeholders may not realise quite how costly non-compliance can become, so making sure they have been informed of how important early-stage fire safety focus is can help to ensure projects stay on track, in terms of cost, timeline and also likelihood that architectural vision is brought to life.

Richard White, Commercial Director, Sertus