Width of doors stairs and escape routes
The building regulations Approved Document B2, ‘Fire safety: Buildings other than dwellinghouses’, suggests that the width of:
- A door (or doorway) is the clear width when the door is open (see Diagram C1);
- An escape route is the width at 1,500 mm above floor level when defined by walls or, elsewhere, the minimum width of passage available between any fixed obstructions;
- A stair is the clear width between the walls or balustrades.
In the case of escape routes and stairs, handrails and strings which do not intrude more than 100 mm into these widths may be ignored (see Diagram C1).
The rails used for guiding a stair-lift may be ignored when considering the width of a stair. However, it is important that the chair or carriage is able to be parked in a position that does not cause an obstruction to either the stair or landing.
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