New high-rises over 18m will need second staircases from Sep 2026

The government has introduced this new threshold after considering the responses to its consultation on the fire safety guidance of the building regulations, known as Approved Document B.

The consultation, which ran from December 2022 until March 2023, received 285 responses. It specifically considered the introduction of second staircases in new residential buildings of 18m and over in England.

The government initially proposed a threshold of 30m+ for the introduction of a second staircase. 25% of respondents agreed with the proposal, whereas 48% of disagreed with it.

Of those who disagreed with the 30m+ threshold:

Despite wide recognition that there is no evidence that shows a single staircase to existing tall buildings is unsafe when designed and maintained correctly, a significant majority of respondents were in favour of the proposal to introduce a threshold to offer greater resilience and increase public confidence.

All building applications will need to conform to the new guidance from 30 September 2026. Any approved applications that do not follow it will have 18 months for construction to begin.

RIBA welcomed the new threshold. The institute's chair of board, Jack Pringle, said: "This marks a crucial step towards a safer built environment for all. It falls short of requiring a second fire-fighting shaft, which our consultation response called for, or evacuation lifts, both of which are vital for emergency evacuation and fire-fighting operations."