A core concept for tall buildings
Earlier this year, we announced that our OFR colleagues were working in collaboration with Matt Brook Architects to design a core for tall buildings – one which would allow for the introduction of second staircases.
Since then, the UK government has confirmed that it will adopt an 18-metre height threshold for second staircases in all new residential buildings. In response, we’ve released updated plans of our second staircase concept – something which will support the viable development of safe, tall buildings in an increasingly difficult construction market. Here, our colleague Rich Rankin tells us more.

Our OFR colleagues have been working with Matt Brook Architects this year to develop a two-stair core design for a series of residential towers in Greater Manchester.
Back in May we gave you a first look at the concept, and this week, we have released updated drawings, culminating in this piece in RIBA Journal. The article talks about how we are maximising safety and accessibility benefits while increasing the useable floorplate by 5% over a typical two-stair design.
The designs show how we have embraced the challenge of incorporating two stairs into high-risk buildings and developed a design which provides a true alternative for all users. The main premise of the concept is the introduction of two interlocking – yet independent – staircases arranged in a double helix around a central, fire-rated wall that separates the two spirals.
In plans, this means the staircases look like a single stair, in a single footprint – which is appealing to developers.
Additionally, the core arrangement considers evacuation of persons of impaired mobility by utilising suitable lifts for self-evacuation, with the lifts separated from each other by passive fire protection and protected by separate smoke control systems to provide places of relative safety while the wait for a lift.
And, each half of the core features a dedicated smoke ventilation system to ensure complete separation – not just to prevent smoke getting into the staircases but to protect the route to the staircase and the route to the evacuation lift in the affected corridor.

It’s a concept that we firmly believe in, one which will give developers a viable option for addressing safety in high rise building development. We will continue to pioneer our designs and work with local planning authorities on the first schemes in which the proposals feature. Watch this space for further updates and in the meantime, you can read the full article here.
Image credits: Matt Brook Architects.