From the end of September, new residential buildings over 18 metres in England must be designed with a second staircase, with provisions for evacuation lifts alongside.
The next set of amendments to Approved Document B takes effect on 30 September 2026. The headline change is that all new residential buildings over 18 metres in England must be designed with a second staircase, and the guidance also includes provisions to support the use of evacuation lifts in blocks of flats.
Existing buildings are not automatically required to retrofit a second staircase. That said, owners of higher risk buildings continue to carry duties under the Building Safety Act and the Fire Safety Order, and those duties do not pause because the new guidance is aimed at new design. The practical weight of the change falls on London and the larger regional cities, Manchester, Birmingham and Leeds among them, since that is where residential development above 18 metres is concentrated.
The part that will catch project teams out is the transitional arrangement. The earlier edition continues to apply where a building notice, an initial notice or a full plans application was given to the relevant authority before 30 September 2026, and where the work has either started and is sufficiently progressed before that date, or starts and is sufficiently progressed within eighteen months of it. Whether a scheme is sufficiently progressed is a question that needs answering now rather than in a year.
For anyone with a scheme close to that boundary, the sensible move is to establish which edition applies, record the reasoning, and build the fire protection requirements into the programme with enough detail that the compliance position is clear to everyone around the table.
A change like this is not difficult in itself. What causes the problems is finding out late which set of rules your scheme falls under, because by then the design is fixed and the programme is committed. Get everyone round the table early, agree the position, and write it into the programme in proper detail. That is what delivers right first time instead of a rework six months down the line.
