Metric Data 11 – Accessible Bathroom and WC
House Extensions BLOG

Accessible Bathroom and WC in Dwellings

In this section of our Metric Data series we will look at accessible sanitary facilities. This refers to designing wheelchair accessible bathrooms and wheelchair accessible WCs.

 

Scroll to the end to download this article as a handy PDF guide!

You can also download the cad files for a small fee by following the link below:

 

The building regulations have varying requirements in terms of accessible sanitary facilities, according to the category you are working towards:

M4 (1) – Visitable Dwellings

M4 (2) – Accessible and adaptable dwellings

M4 (3) – Wheelchair user dwellings

 

Category M4 (1) is considered to be a compulsory requirement, and the other categories optional unless a condition is imposed on a new development as part of the process of granting planning permission. If no condition is imposed the dwelling will only need to meet requirements for M4 (1),  but if the condition is imposed to M4 (2) or (3) it may be that specific dwellings in a development must comply.

 

My personal feeling is that all dwelling should be as accessible as possible, or at the very least as adaptable as possible. I think we should strive to do more than the bare minimum that our regulations set out and aim to achieve better accessibility and performance in our buildings regardless of government targets.

 

So for this reason, we will look at making the WC accessible and the bathroom accessible to wheelchair users, and work from section M4 (3) wheelchair user dwelling.

Be sure to always refer to the Building Regulations Approved Documents when designing accessible layouts and facilities.

 

Building Regulations Requirements for Accessible Bathrooms and WCs

 
 

General Provisions for accessible bathrooms and WCs

 
Some of the general provisions for wheelchair accessible sanitary facilities according to Building Regulations Approved Document Part M include:
  • Any dwelling with four or more bed spaces must provide a minimum of two WCs in separate bathrooms or WC/cloakrooms.
  • Every room that contains a level access shower is constructed as a wet room.
  • Any walls, ducts and boxing in any sanitary facility must be strong enough to support grab rails, seats and other adaptations.
  • The ceiling structure must be strong enough to support an overhead hoist capable of carrying 200kg.
  • WC flush controls must be positioned in front of the cistern on the transfer side and can be easily gripped.
  • WC pans should be a minimum of 400mm high.
  • Basins and sinks should be wall hung, typically 770-850mm above floor level, with a clear zone beneath to allow wheelchair users to approach easily.
 
 

Accessible WC on the entrance storey

 
A wheelchair accessible dwelling must have, on the entrance storey, a wet room that contains a WC, a basin and an installed level access shower.
If the dwelling provides both a bathroom and WC on the same storey, the WC does not require a shower (See Part M for details on second WC).
The door to the WC must open outwards.
WC Access zone WC

WC Access zone (entrance storey WC)

WC Access zone with shower

WC Access zone with shower (entrance storey WC)

Access Zone Shower (entrance storey WC)

Access Zone Shower (entrance storey WC)


Wash basin access zone (WC and Bathroom)

Wash basin access zone (WC and Bathroom)

Accessible WC example

Bathroom Facilities

 
To have suitable bathroom facilities for a wheelchair user a dwelling much comply with the following:
  • Dwellings with up to four bedspaces should have a minimum of one bathroom containing a WC, basin and a level access shower, with the potential for a bath to be installed, (unless a bath is provided in addition to the shower, or in another bathroom on the same storey). 
  • The WC, basin, shower and bath must have suitable clear access zones as shown in previous diagram.
  • Dwellings with five bed spaces or more must contain both a usable bath and a level access shower. 
  • The level access shower must be positioned in a corner to enable a shower seat to be fitted on one wall with the shower controls on the adjacent wall. 
  • The bathroom provides a minimum 1500mm clear turning circle.
WC Access Zone (bathrooms)

WC Access Zone (bathrooms)

wc access zone with shower (bathrooms)

wc access zone with shower (bathrooms)

bath access zone (bathroom)

bath access zone (bathroom)

shower access zone (bathroom)

shower access zone (bathroom)

Accessible bathroom example

Other Tips

 
  • Specifying underfloor heating allows the floor to dry faster
  • Safety glass for the shower screen can also have frosted manifestations
  • Ensure the bathroom door lock is operable from the outside
  • All walls should be constructed to be strong enough to take fittings and rails
  • Bath installations should include a transfer area at the end of the bath and ensure taps are fitted to be accessible to the nearest corner.

 

Don’t forget to download your PDF of this blog post, and get hold of the accompanying cad files too!

You might also be interested in

We have loads of other useful posts in our Metric Data Series. Make sure you check them all out.

Metric Data 01 – Average Dimensions of Person Standing FI
Metric Data 03 - Average dimensions of wheelchair user FI
Metric-Data-05-Approach-Entrance-and-Horizontal-Circulation
Metric data 07 wheelchair accessible living area FI
Metric Data 09 - Kitchen Standard Sizes
Metric Data 11 Accessible Bathroom and WC FI
Metric Data 02 – Average Dimensions of Person Sitting FI
Metric Data 04 Circulation and space
Metric Data 06 wheelchair accessible dwelling FI
Metric Data 08 - Standard Furniture Sizes
Metric-Data-10-Kitchen-Standards-for-Wheelchair-Users-FI
Metric Data 12 - Standard Door Sizes

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