By Nick Atkinson, Director at Ambar Kelly
The UK construction industry is somewhat at a standstill right now, with the Building Safety Regulator’s (BSR) gateway approval process currently taking an average of 36 weeks per project and only 10% actually receiving approval. With the BSR set to take a firmer approach to reject any applications that aren’t ‘making the bar straight away’, the importance of architects and contractors taking a safety-first approach when it comes to riser design in tall buildings has never been greater. Nick Atkinson, Director at Ambar Kelly, underscores the importance of utilising a safety-first approach in tall building design and reveals how RiserSafe® is designed to be specified early and requires no maintenance or adaptation during the build to deliver safety reliably.
With contractors and architects under considerable pressure to meet tight deadlines and budgets, safety-critical components, such as the early specification of riser flooring and the design of the riser shaft, can often be overlooked.
However, with ever-tightening building regulations and standards as a result of the BSR’s focus on building safety, especially in high-risk buildings (HRBs), this is a recipe for disaster.
Ultimately, failing to design with safety in mind is designing to fail. In fact, if riser flooring is not specified at the design stage, projects may face significant delays, costly reworks, increased risks and regulatory non-compliance.
Conversely, incorporating riser flooring into riser shaft design at the very beginning enables a project to be delivered holistically, with each package coordinated around compliance, safety and logistics. As a result, costs will be controlled, working at height risks will be eliminated, the spread of fire and smoke prevented and buildability improved.
Removes the need for costly adaptations
Ignoring safety during the design stage can often lead to costly spending further down the line – typically totalling far more than the initial outlay would be and increasing the financial responsibilities for the main contractor.
Incorporating riser flooring into the initial riser shaft design, through the use of Building Information Modelling (BIM) and federated models, can streamline MEP service installation and reduce on-site clashes. Consequently, the need for rework is significantly lowered – expediting the design and installation process to support faster project delivery.
Compliance with regulations
The Grenfell tragedy led to the removal of references to the national classification system for fire resistance, known as BS476 Parts 6 & 7. Furthermore, projects would need to adhere to rigorous regulations to pass through Gateways Two and Three – checkpoints designed to strengthen regulatory oversight of higher-risk building (HRB) design and construction and increase transparency.
The incorporation of non-combustible modular riser flooring into the riser design and early collaboration between all members of the project can ensure compliance with the current building regulations and ensure smoother progress through the gateways without the need for retrofit or unplanned redesign.
Assuring safety after handover
Grenfell Tower highlighted the importance of material specification in regard to the spread of fire and smoke throughout a building, with the addition of combustible cladding to the original concrete structure creating a cavity. When combined with inadequate fire stopping, this created a chimney effect – similar to a riser shaft.
The combustible nature of the cladding material, similar to glass reinforced plastic (GRP) – commonly used in riser shafts for fall prevention – then fuelled the fire’s spread. The resultant heat caused cladding distortion, allowing the fire to pass around the fire stopping that had been used, equivalent to a riser door being left open.
This highlights the need for an early and holistic approach when it comes to riser design. In fact, the prompt specification and incorporation of non-combustible materials, such as A1-rated modular riser flooring, helps reduce the spread of flame and smoke, protecting those working on-site and future building users and occupants.
Full project coordination and informed material choice
Frame contractors, under pressure to save costs, may choose inappropriate solutions, such as glass reinforced plastic (GRP), based solely on a focus on fall protection and short-term savings. As a result, the bigger picture of long-term maintenance, compliance and fire performance can be ignored.
For example, while GRP may seem cheap initially, it requires structural steel to support it when cut for services, and needs additional strengthening and working at height adaptions. Indeed, GRP typically costs around 0.3% of the total build value, compared to 0.2% for RiserSafe® projects.
Through 3D modelling and coordinated digital design, all elements of the riser shaft, including fire protection, structural interface, and MEP routing, can be integrated seamlessly. This enhances collaboration between designers and contractors and results in smarter, safer decision-making from the outset.
RiserSafe® designed to be specified early
As non-combustible modular riser flooring that’s designed to meet any project’s interface requirements, RiserSafe® is able to be incorporated early into the building design.
In addition to preventing falls from height and allowing other disciplines to continue working without hindrance, it also reduces the risk of smoke and fire spreading through the riser shaft.
Thereby, the incorporation of modular riser flooring systems, such as RiserSafe®, into riser shaft design can provide peace of mind, eliminate nasty cost surprises in the future and enhance safety.
Taking a safety-first approach shouldn’t just be best practice; it needs to be a moral and legal imperative. Incorporating riser shafts into the design at the earliest possible stage ensures a safer and better built environment that protects everyone – not just those working on-site but anyone who lives and works in the buildings for the many years ahead.