One Nine Elms, London Fire Engineering Solution

A bespoke high rise development requiring a bespoke fire engineering solution


The two iconic towers at One Nine Elms occupy prime position at the gateway to the Nine Elms development. At 56 storeys, the observation deck located at the top of the City Tower will offer its residents and guests unrivalled views of London’s most famous landmarks.

The challenge however was how to develop a suitable fire engineering design that could accommodate the flexibility of the space, limit the impact on the rest of the building and above all provide a robust strategy for the safety of the end users.


The result is one of the world’s tallest true single stair mixed use buildings. By avoiding a convoluted scissor stair arrangement and instead developing a strategy based in part on evacuation lifts, Sweco’s engineers were able to develop a solution that cut the total evacuation time in half and limit potential disruption to fire fighters.

In developing the strategy in this way, the professional team were able to rationalise the core design and deliver c.10% more residential accommodation.

In order to safeguard the occupants at the top of the building a series of smoke control strategies have been incorporated, which account for, amongst other things, the potential dangers associated with wind driven fires. This is of particular concern in high rise developments and Sweco have drawn from recent case studies and industry research to help inform the strategy.

The unique design uses a combination of positive pressurisation, mechanical extract and natural ventilation, which together with suppression, serve to protect against internal and external fire and smoke spread. The solution also overcomes traditional issues associated with the commissioning of such systems and streamlines the design so that the systems can be efficiency coordinated. In all, the varied approach ensures a level of resilience unseen in other high rise developments and reflects Sweco’s commitment to delivering solutions that go far beyond normal standards both in terms of safety and design.