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Bathrooms in Residential Dwelling Units – What Needs To Be Done?


Janis Kent, Architect, FAIA, CASp © January, 2024

In covered multi-family housing that is privately owned, without any public programs or funding, bathrooms within the dwelling units are required to be adaptable according to FHA. One can have a choice of Specification A or B bathrooms, or under CBC 11A Option 1 or 2. Note that if you follow CBC Option 1, if might not meet the FHA requirements. The issue that gets more complex is in residential dwelling units where the facility is owned or is a program of a public entity, or receives a form of public funding, where the bathroom is also controlled by the ADA Standards requirements.

Public Dwelling Units with Mobility Features

Dwelling Units With 1 Bathroom

Presuming the dwelling unit is located in a public residential facility, the bathroom is relatively straight-forward if there is just one in the unit. ADAS is applicable to the mobility dwelling unit and the bathroom needs to be accessible. The door needs to be accessible as well as its maneuvering space on both sides. The door swing can intrude into the turning space without limit if there is a 30″ x 48″ clear floor space beyond the door swing. It can also swing over clearances for other fixtures, but the fixtures can not be located in the door maneuvering space – just the fixture clearance can overlap. There is a bit more leeway in toilet fixture height and the toilet clear floor space than in public restrooms. Also, grab bars are not required to be installed, although the backing is to be provided. Tub seats are to be provided, but shower seats only are required to have blocking installed. If the mobility dwelling unit has just one bathroom, the accessible route can not pass thru the bathroom, but it does need to be located on the accessible route. The CBC has a few additional requirements for dwelling unit bathrooms as well.

Dwelling Units with More Than One Bathroom

The issue that comes up is, if the mobility dwelling unit has more than one bathroom. The accessible bathroom is to have one of each type of fixture accessible and located within the same area without having to travel to other parts of the unit or other bathrooms. Section 809.4 under ADAS appears somewhat cryptic when just reviewing the second sentence. But the third sentence specifically states they are to be located in the same toilet and bathing area so additional travel is not required.

809.4 Toilet Facilities and Bathing Facilities. At least one bathroom shall comply with 603. No fewer than one of each type of fixture provided shall comply with applicable requirements of 603 through 610. Toilet and bathing fixtures required to comply with 603 through 610 shall be located in the same toilet and bathing area, such that travel between fixtures does not require travel between other parts of the residential dwelling unit. 

Some interpret this to mean you can have an accessible tub in one bathroom and an accessible shower in the other, but only one bathroom is required to be fully accessible. In fact, CBC specifically states if you have a tub in the accessible bathroom and a shower in the subsequent one, both the shower and the tub fixtures are required to be accessible under 11B-809.4.1. But what some miss is that the accessible fixtures are to be located in the same bathroom both per ADA and 11B-809.4.

So be careful when designing, that if a mobility dwelling unit has showers and tubs in multiple bathrooms, one of each fixture is to be accessible in the same bathroom, not dispersed. The other secondary bathrooms are not required to be accessible, although there are still requirements. The door and its maneuvering space are to be compliant and there is to be a turning space in the secondary bathrooms if they are located on an accessible route. The electrical is to be within reach range, and blocking is to be provided for compliant grab bars for future installation. The main difference is, the individual fixtures within secondary bathrooms are not required to be accessible or have the required clear floor space. There is no direction on which bathroom to make mobility accessible, so some thought should be given as to which one is most useful to be designed in this fashion.

Public Dwelling Units with Non-Mobility Features

The non-mobility dwelling units in covered public residential are to have usable bathrooms complying with FHA. Under CBC, bathrooms located on an accessible route are to comply with the 11B adaptable requirements for the route, the doors, reinforcement for grab bars, and reach ranges for electrical. One of the bathrooms is to meet the CBC 11B adaptable requirements for the 30″ x 48″ clear maneuvering space beyond the door swing, and one of each type of fixture with its requirements and clear floor space. If both a shower and a tub are located in the same bathroom, then only one bathing fixture is required to be adaptable. If there is more than one bathroom in a non-mobility unit, and the adaptable bathroom has only a tub, if there is a shower in another bathroom, then under CBC, the shower is to also comply. 

If a powder room is located on an accessible route, it is to comply with the requirements for secondary usable or adaptable bathrooms. If the powder room is the only toilet facility on an accessible route, then it is also to comply with the fixture requirements for toilets and lavatories and the maneuvering space beyond the door swing.

When designing multi-family housing, it is essential to understand the funding and programs that support the facility. If there is any public programs or funding, then differentiate which units are mobility, and if they have more than one bathroom inside the unit, determine which one is to be accessible. For the non-mobility dwelling units with more than one bathroom, decide which one is to be the usable or adaptable bathroom. Note that dwelling units for social service center establishments follow the ADA dwelling unit bathroom requirements regardless of the program or funding sources with some modification for large sleeping rooms having more than 25 beds. Under CBC, tub seats are to be provided, not just the blocking. Just some things to consider.

Be aware that your local City or County may have additional requirements that are more restrictive than the State or Federal requirements. Also, this article is an interpretation and opinion of the writer. It is meant as a summary – current original regulations should always be reviewed when making any decisions.

© Janis Kent, FAIA, Architect, CASp 2024