How Will The Second Staircase Rule Impact The Construction Sector?
Looking for your next balcony? We're here to help you adhere to UK regulations and get exactly what you need
Introduction
The Second Staircase Rule marks a defining moment in the evolution of UK building safety regulations. Introduced through an amendment to Approved Document B in March 2024, the rule mandates the inclusion of two staircases in all new residential buildings over 18 metres in height. This decision, rooted in lessons learned from high-profile fire incidents, seeks to improve evacuation strategies and enhance resident safety.
For architects, contractors, and developers navigating the complexities of UK building regulations for staircases, this new requirement adds both responsibility and opportunity. It is more than a regulatory update; it is a shift toward best practices in building stairways, staircase safety, and British Standards for staircases.
Gatehouse Architectural supports clients with the design, manufacture and installation of staircase systems that comply with the latest building regulations, including bespoke steel and glass staircases, stair balustrades, and dual stair solutions tailored to both residential and commercial environments.
The government’s guidance, published in the official Building Regulations 2010 - Amendments to the Approved Documents - Approved Document B: Fire safety Volumes 1 and 2, sets a clear course for compliance, encouraging early engagement with the building regulation for stairs in both design and planning stages.
What Is The Background and Legal Context?
Approved Document B is the cornerstone of fire safety regulation in England, setting standards for means of escape, smoke control, and fire-resisting construction. The newly mandated second staircase requirement builds upon the Building Safety Act 2022 and aligns with broader fire safety reforms. Initially proposed with a 30-metre threshold, the final regulation now applies to buildings with a top storey over 18 metres, harmonising with the criteria for high-risk buildings.
This update follows consultation with experts, including the National Fire Chiefs Council and RIBA, who advocated for improved evacuation access. It acknowledges the importance of having not just a single staircase, but two flights of stairs to ensure redundancy in emergency routes, particularly in high-rise residential environments. It also highlights a growing focus on building staircases not only for accessibility and function, but for critical life safety.
What is the Second Staircase Rule?
The Second Staircase Rule requires that all new residential buildings exceeding 18 metres in height must be served by at least two independent staircases. This means any building at this scale must go beyond the traditional basic staircase design and integrate a dual means of vertical escape.
This rule is central to fire safety planning. In emergencies, especially in buildings with 20 or more storeys, or what some may refer to as “20 stairs", a second stairwell can be the difference between safe evacuation and life-threatening entrapment.
Importantly, interlocked or scissor stair designs are not acceptable substitutes for separate escape routes. The guidance is specific: staircases must be independently accessible, protected by appropriate fire doors, and ideally integrated with evacuation lifts within enclosed evacuation shafts.
Key Requirements Under the Rule
For professionals working with building control staircase regulations, understanding the exact criteria is crucial. The rule applies to:
- Buildings over 18 metres tall, defined by the top storey height from ground level.
- Stairwells that must be independent and protected, with no interlocking features.
- Situations where protected lobbies, fire doors, and smoke control systems are essential.
- Designs that support the inclusion of evacuation lifts within evacuation shafts.
While these requirements represent a shift from more traditional domestic stairs building regs, they are consistent with global best practices and the expectation that future tall buildings will be designed with both primary and backup means of escape.
What Is The Implementation Timeline?
To allow for industry adaptation, the government has established a 30-month transition period ending 30 September 2026. Until then, developers can choose whether to follow the old or new guidance.
Projects approved under the existing regulations will have 18 months to begin construction. If no significant progress is made, those projects must resubmit under the new standards, including the provision for 2 staircases. This gives clarity for planning authorities and developers alike, particularly for designs previously paused or awaiting revised stair regulations.
Impact on the UK Construction Industry
The construction sector must now evaluate how the second staircase rule will affect space planning, project viability, and overall design.
Incorporating a double staircase, whether a double return staircase, side-by-side arrangement, or separated stair cores, impacts usable floor area. For high-density residential schemes, this can reduce net saleable space. For design teams working with building regulations staircases UK, the implications are both architectural and economic.
Cost increases are expected due to the expanded footprint and enhanced fire stair regulations UK. Additionally, EIA statements may need revision, particularly if building height, massing, or internal layouts are affected.
Despite these hurdles, many stakeholders have welcomed the clarity and safety improvements. The rule brings the UK in line with safety standards in countries that already require dual staircases for buildings above specific thresholds.
Benefits and Rationale
This rule’s main benefit is obvious: enhanced safety. By introducing a second vertical escape route, residents are afforded an alternative path in emergencies. This can be particularly crucial in buildings with extended corridors, mixed uses, or populations with limited mobility.
It also restores public trust in residential developments, sending a clear signal that building stairways and escape strategies are being taken seriously. The move away from single staircase buildings acknowledges historic shortfalls and embraces future-ready thinking in line with international norms.
Moreover, the update integrates well with existing British Standards staircases and current best practices in fire safety codes for office staircases, forming part of a holistic approach to safer buildings.
Challenges and Criticisms
The primary concern from developers revolves around design limitations and increased construction costs. Some projects, particularly in constrained urban sites, will find it challenging to accommodate two stairwells without reducing unit numbers or changing layouts.
There’s also debate about how flexible the interpretation of the rule can be. Some developers argue for greater guidance on acceptable alternatives, such as interlocked stair cores. Others point to the complexity of aligning building regulation staircases with local planning frameworks.
Nevertheless, with a clear timeline and guidance document, many of these uncertainties are expected to be resolved through engagement with building control and fire consultants.
Compliance Tips for Developers and Designers
For those designing or delivering residential buildings over 18 metres, early compliance is crucial. Engage with building control staircase regulations from RIBA Stage 2 onward, ensuring stairwell design is coordinated with other core services such as lifts and vertical risers.
Work closely with fire safety engineers to develop layouts that respect both the minimum stair going UK and the maximum step height UK. Refer to current UK building regulations for stairs, including Part B and Part K, to ensure comprehensive compliance.
Consulting with experienced metalwork and stair specialists, like Peter Marshall Steel Stairs, can help mitigate cost and programme risks. Their input on prefabricated solutions, space-saving options, or modular components can streamline compliance with staircase building regs UK.
Document all decisions thoroughly. Approval hinges not only on what is built, but how well it is justified. This includes lift lobby protection, evacuation modelling, and stair access across all floors.
Conclusion
The Second Staircase Rule marks a pivotal evolution in UK staircase regulations, embedding dual escape provisions into the future of residential design. Its introduction reinforces a culture of proactive safety and places the UK among global leaders in tall building standards.
For developers, the key to successful navigation lies in early planning, consultation, and design coordination. The rule doesn’t simply add another flight of stairs, it elevates the expectations of what safe, compliant, and resilient buildings should deliver.
As stated in The Building Regulations 2010 - Amendments to the Approved Documents - Approved Document B: Fire safety Volumes 1 and 2, the rule isn’t just a formalit, it’s a blueprint for saving lives.
This article references official government guidance and aligns with ongoing updates to UK fire safety and building codes.
More info
From standard and bespoke ranges of architechtural and industrial staircases, balustrades and balconies to beautiful domestic feature metalwork, we've got all the information you need.
