ADA bathtub requirements

The requirements at a glance

Heights are measured from the finished floor, except the lower back bar, which is measured from the rim. The Standards give no tub size, and the Access Board’s guide confirms they set no rim height.

The clear space and the end-wall bars, drawn

The clear space is what lets someone in a wheelchair pull up alongside the tub and slide onto the seat. It runs the full length of the tub and is 30 in wide, measured out from the tub (607.2). The Access Board’s guide to the Standards recommends keeping the sink out of it, even though one is allowed at the control end, so the controls stay easy to reach. With a permanent seat at the head end, the space has to run at least 12 in past the head-end wall, so the person can line up with the seat.

The same space is one of the clearances an accessible bathroom has to fit, along with the 60 in turning space and the toilet’s clear space; they may overlap (603.2.2). How that adds up in a whole room: ADA bathroom layouts.

The grab bars on the back wall

The two back-wall bars are the same in both cases: the upper one with its top 33 to 36 in above the floor (609.4), the lower one 8 to 10 in above the rim of the tub. Where they sit along the wall depends on the seat:

• Removable in-tub seat (607.4.2): each back bar is at least 24 in long, starts no more than 24 in from the head-end wall and ends no more than 12 in from the control-end wall. Add a bar at least 24 in long on the control-end wall and one at least 12 in long on the head-end wall, both at the front edge of the tub.
• Permanent seat at the head end (607.4.1): each back bar runs to within 15 in of the head-end wall, so it can be reached from the seat, and to within 12 in of the control-end wall. The control-end bar is the same, at least 24 in at the front edge. There is no head-end bar: the seat’s wall gives the back support.

Keep anything that sticks out from the wall at least 12 in above a grab bar and 1½ in below it; shower controls, fittings and other grab bars may come as close as 1½ in above (609.3). The ADA doesn’t require a vertical bar at a tub, but the Access Board’s guide notes that the ICC A117.1 standard, which the International Building Code references, does: an 18 in vertical bar. Grab bar heights around the rest of the bathroom are in our ADA bathroom requirements checker.

Controls, hand shower and shower doors

• Controls go on an end wall, not the back wall: below the grab bar and above the rim, and between the open side of the tub and its centerline, so they can be reached from outside the tub (607.5). They must work with one hand, without tight grasping, pinching or twisting of the wrist, and with no more than 5 lb of force (309.4). The guide counts knobs that need a full grip and a turn, shower knobs included, as controls that don’t comply.
• The hand shower has a hose at least 59 in long and can be used fixed or held (607.6). Its on/off control has a non-positive shut-off, which slows the water but doesn’t fully stop it. If it rides on a vertical bar, the bar must not get in the way of the grab bars. Water from it is limited to 120°F. Unlike an accessible shower, a tub has no fixed-head option.
• Doors and screens may not block the controls, the hand shower or a transfer onto the seat, and there can be no track on the rim of the open side (607.7). That rules out sliding doors that run in a track on the rim; a curtain has no track.

Who has to meet these, and what they leave out

• Private homes don’t. The Access Board’s guide says private residential housing isn’t covered by the ADA; government-owned or operated housing and some privately owned housing, such as housing at a place of education, are. In a covered dwelling unit, at least one bathroom has to meet the Standards, with one of each fixture type (809.4), and the tub’s grab bars may be left off if the walls are reinforced for them later (607.4, exception 2).
• Hotels. Accessible guest rooms come in two kinds: with roll-in showers and without them (Table 224.2). A room without a roll-in shower still needs one accessible bathtub or shower (806.2.4); when that fixture is a tub, it has to meet 607.
• One is enough. Where a bathing room has several tubs or showers, at least one tub meeting 607 or one shower meeting 608 has to be provided (213.3.6).
• Not set: the size of the tub and the height of its rim. The guide suggests making the outside wall of the tub the same height as the seat, 17 to 19 in, for easier transfers. Spa tubs follow the separate spa rules, not 607.

Thinking of a roll-in shower instead of a tub? Its sizes are in the ADA checker, and our tub to shower planner shows which shower bases fit a tub’s space. Tub sizes to start from: standard bathtub size.

Questions people ask