How Wide Does a Corridor Need to Be to Turn

A corridor used by a wheelchair needs an unobstructed width of at least 1200 mm to carry one chair, and either 1800 mm or passing places 1800 mm wide and 1800 mm long at reasonable intervals for two wheelchair users to pass. Turning is a separate figure. Department for Transport guidance for transport buildings gives 1200 mm by 1200 mm as the minimum for a right-angle turn along a corridor, 1600 mm by 2000 mm for a 180-degree turn within one, and 1500 mm by 1500 mm as the space in which a skilled manual wheelchair user can turn right round. A corridor that is wide enough in a straight line can still fail at every door and junction along it.

What is the difference between a corridor width and a turning space?

A corridor width is measured along the line of travel: the clear distance between the walls, with any projection into the space, such as a radiator, a column or a fire hose, left out of the figure. Approved Document M Volume 2 counts only the unobstructed width. A turning space is measured as a rectangle at a specific point, usually a junction or the area in front of a door, where the chair has to change direction rather than continue straight.

Inclusive Mobility, the Department for Transport's guide to best practice, notes that the 1500 mm by 1500 mm space is enough for a skilled user of a manual chair but not for a chair pushed by an attendant, a larger outdoor electric chair with a turning circle of around 2420 mm, or a user with an extended leg rest. At a door, Approved Document M adds its own figure: an unobstructed space of at least 300 mm on the pull side between the leading edge of the door and any return wall, so a wheelchair user can reach the handle without the footrest hitting the wall. A corridor can be exactly 1200 mm wide for its whole length and still trap a chair at a door if that space is missing.

Why does a 90-degree turn need more room than a straight corridor?

A wheelchair does not pivot on a single point the way the word turning circle suggests. A manual chair needs room to roll forward, angle the front castors and roll back before completing a turn, and that manoeuvre uses more floor area than the chair's own footprint. A powered chair still needs clearance for the footplates, which project ahead of the main wheelbase and can catch a wall or a door frame the seated user cannot see.

A corridor that meets a door at a right angle, rather than running straight into it, needs turning room on the corridor side of the door, not just the doorway's own clear opening. Commissioning custom woodwork and fitted furniture close to a corridor turn is one of the most common ways this space disappears after a building has been checked once and never checked again.

What should the figures be at a junction or a lift lobby?

Approved Document M asks for an unobstructed manoeuvring space of 1500 mm by 1500 mm in front of each lift, or a straight access route 900 mm wide, and names corridor junctions as a sensible place for the 1800 mm passing places. It also asks that elements such as columns, radiators and fire hoses do not project into the corridor, or, where that cannot be avoided, that a visually contrasting guard rail directs people around them, and that doors opening towards a major access route or escape route are recessed so they do not project into the corridor when fully open. Each of these narrows the usable width at exactly the point where more room, not less, is needed.

A fire door held open on a hold-open device can also swing into the turning space when released, and a corridor that measures correctly with the door open can fail the same test with the door closed. The test has to be done both ways: door open, and door released under its own closer.

How does furniture and storage reduce a measured corridor?

A corridor measured empty on a drawing rarely stays empty in use. A fire extinguisher on a bracket, a defibrillator cabinet, a stack of chairs waiting to be put away, or a cleaning trolley parked for the duration of a shift can each take several hundred millimetres out of a corridor that was wide enough on paper. The reduction matters most at a turn, where the full width was already needed and where an obstruction is also harder to see from a wheelchair seat lower than a standing adult's eye line.

A corridor audit that only checks the architect's drawing, and never walks the route with a tape measure on the day, will miss this category of fault entirely. The drawing shows the building as designed; the obstruction shows the building as used.

What does the Equality Act 2010 require once the building already exists?

The Equality Act 2010 does not set the 1200 mm or the 1800 mm figures itself; those come from Approved Document M, which applies to new work and refers to BS 8300 for further detail. Approved Document M itself accepts that narrower corridors, or local narrowing at an archway, might be reasonable in existing buildings. What the Act requires is that a service provider makes reasonable adjustments so a disabled person is not placed at a substantial disadvantage, and an existing corridor that is narrower than current guidance is not automatically unlawful on that basis alone. What turns a narrow corridor into a breach is the refusal to make a reasonable adjustment once the barrier is known: moving a fixed obstruction, relocating a storage point, or widening a single turn at a frequently used door.

A building manager who has walked the corridors with a tape measure, recorded where turning room is missing, and acted on the easiest fixes first, usually spends very little to clear the worst points. Moving a cabinet or rehanging a notice board costs nothing like widening a wall, and it is often the obstruction, not the structure, that is failing the turn.

What to measure before relying on a corridor

Walk the route a wheelchair user would take, not the route a drawing shows. At each door, measure the clear width of the corridor on the approach side, the space beside the leading edge on the pull side, and the turning room in front of the door with any closer-held leaf in its resting position. Note anything fixed close to a turn: a radiator, a cabinet, a trolley point. Record the figures in millimetres against the benchmarks in Approved Document M and Inclusive Mobility, and treat a corridor that passes in a straight line but fails at its doors as a corridor that has not yet been checked.