Accessible WC Calculator - Doc M Wheelchair Toilet Dimensions
Check whether your wheelchair-accessible toilet layout meets Approved Document M and BS 8300 requirements.
How We Calculate This
This calculator checks your proposed accessible toilet dimensions against the requirements of Approved Document M (Volume 2: Buildings other than dwellings) and BS 8300:2018.
Dimension checks
- Room width: Minimum 1500mm for wheelchair accessible WC
- Room length: Minimum 2200mm for wheelchair accessible WC
- Turning circle: 1500mm diameter clear floor space
- Door width: Minimum 950mm effective clear opening
Grab rail positions
Grab rails must be positioned per the standard Doc M layout. Drop-down rails are provided on the transfer side (the side the wheelchair user approaches from). Fixed rails on the opposite side. All rails at 680mm above finished floor level, 320mm from the centre line of the WC pan.
WC types assessed
- Unisex Accessible WC: Full wheelchair accessible, Doc M compliant (1500 x 2200mm)
- Ambulant Disabled WC: For ambulant users with mobility aids (800 x 1500mm)
- Enlarged Cubicle: Larger than standard, for mobility aid users (1200 x 1500mm)
Frequently Asked Questions
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Last updated: March 2026
All calculations are estimates. Verify with your supplier.
