Finance Editor, Kael Tripton Ltd - LBS MBA - Verified against FCA Handbook: 14 June 2026
Quick answer
Part M of the Building Regulations (Approved Document M) sets minimum accessibility standards for new buildings and extensions. For new dwellings, three categories apply: M4(1) Visitable, M4(2) Accessible and adaptable, and M4(3) Wheelchair user. Minimum door widths: 750mm clear for M4(1), 850mm for M4(2). Local authorities can require higher categories via planning conditions.
What Is Part M of the Building Regulations?
Direct answer
What does Part M of the Building Regulations require?
Part M (Approved Document M, gov.uk) sets accessibility standards for new buildings. For new dwellings: M4(1) is the baseline (750mm clear doorways), M4(2) requires 850mm clear doorways and adaptable features, M4(3) is full wheelchair user standard. Local authorities can require higher categories through planning conditions. Non-domestic buildings need accessible toilets and level or ramped access.
Identify which Part M category applies
For new dwellings: M4(1) is the baseline. Check planning conditions to see if M4(2) or M4(3) is required. For non-domestic: standard Part M access requirements apply.
Check door widths at design stage
Ensure all doorways meet minimum clear opening widths before work starts. Changes after construction are expensive.
Design level or ramped access
Part M requires level or gently ramped access to entrances. Maximum ramp gradient for M4(1) is 1:20 for short ramps or 1:15 for longer distances.
Install accessible toilet facilities
For non-domestic buildings, ensure at least one unisex accessible toilet complying with Part M dimensions is provided.
Get Building Control approval
Submit plans showing Part M compliance to Building Control before work starts.
| Category | Who it applies to | Key requirements |
|---|---|---|
| M4(1) Visitable | All new dwellings (baseline) | 750mm clear doorways, level or ramped access, ground floor WC provision |
| M4(2) Accessible and adaptable | Optional -- can be required by planning | 850mm clear doorways, level access shower, wider circulation spaces |
| M4(3) Wheelchair user dwellings | Optional -- high standard | Full wheelchair access, turning circles, ceiling hoist provision |
| Non-domestic Part M | New non-domestic buildings | Level/ramped access, accessible toilet, hearing loops, clear signage |
Frequently Asked Questions
What is Part M of the Building Regulations?
Part M of the Building Regulations (Approved Document M) covers access to and use of buildings. It sets minimum standards to ensure that buildings are accessible to people with disabilities and that facilities such as toilets, door widths and ramps meet minimum dimensions. Part M applies to new dwellings, extensions to dwellings and new non-domestic buildings. For new dwellings, Part M introduces three categories: M4(1) Visitable dwellings, M4(2) Accessible and adaptable dwellings, and M4(3) Wheelchair user dwellings.
What are the three categories of accessible housing under Part M?
Part M4(1) is the baseline standard for all new dwellings -- they must be visitable by people in wheelchairs. Part M4(2) (optional requirement) sets higher standards for accessible and adaptable dwellings, requiring wider doorways, level access showers, and provision for future adaptations. Part M4(3) (optional requirement) sets the highest standard for wheelchair user dwellings, requiring full wheelchair access throughout. Local authorities can require M4(2) or M4(3) through planning conditions.
What door width is required under Part M?
Under Part M, minimum clear opening widths for doorways depend on the approach direction. For M4(1) dwellings: 750mm minimum clear width for a standard approach, 775mm for a leading edge approach. For M4(2) dwellings: 850mm minimum clear opening width for all doorways. External doors must have a minimum 775mm clear opening width under M4(1). These are minimum requirements -- wider is always preferable for accessibility.
Does Part M apply to extensions?
Part M applies to extensions to non-domestic buildings where the extension includes a principal entrance or entrance used by the public. For domestic extensions (home extensions), Part M does not automatically apply in the same way as for new dwellings -- the extension must meet the relevant standards for the type of work. However, new wetrooms or accessible bathroom facilities in extensions should consider Part M4(2) standards even when not required.
What is a compliant disabled toilet under Part M?
For non-domestic buildings, Part M requires a minimum unisex accessible toilet of 2200mm x 1500mm with a toilet height of 480mm, a washbasin to the side of the toilet, horizontal grab rails, an outward-opening door or sliding door, and a call for help system. The toilet must be on the same level as the main entrance or accessible by lift. Space for a 1500mm turning circle must be provided.
Primary sources
Kael Tripton Ltd is registered with the Information Commissioner's Office under registration number ZC135439.
