While the basic activity of the bathing/showering center is cleansing the body, there is a wide range of associated activities that take place in this area.
The bathtub, shower and tub/shower combination are the main fixtures, all of which have their own related planning considerations. The following recommendations are excerpted from the book “Bath Planning,” part of the NKBA Professional Resource Library.
Bathtubs come in several sizes. The size of a traditional standard tub or tub/shower combination is 32-in. by 60-in. This size will fit in most full bathrooms. However, it does not necessarily meet the needs of the user, so it is important to discuss tub size with the person(s) who will be bathing.
A tub bath may be taken by simply sitting in the tub. Knees might be outstretched or bent at an angle, but the back is generally perpendicular to the bottom of the tub. Leaning back and relaxing in the tub requires an angled contour to support the user’s back. The appropriate length of the tub should be determined by the leg length of the user. A short woman might slide under the water if her feet do not reach the end of the tub. A tall woman may never be able to lean back and relax without her bent knees raised out of the water.
Longer and shorter tubs are available, and tubs come in different depths that might make the bath more comfortable. Smaller square tubs might also be appropriate for shorter people. If there are multiple users at different times, a compromise in tub size will be needed.
Two people may want to use the tub at the same time. Longer and wider tubs are available for this purpose. Sitting side-by-side requires a 42-in.-wide tub. Sitting opposite requires a 36-in.-wide tub. Often these will be jetted tubs, used sporadically. Soaking tubs which are often deeper, may not be jetted.
Wherever the tub is placed, it is recommended that at least a 30-in. clear space be planned along the side of it. If dressing occurs in front of the tub, more space is needed. A 42-in. to 48-in. dressing circle will allow room to dry off and put on undergarments.
Building codes allow a minimum of 21 inches in front of the tub, but this will be tight for many users. If a parent is helping bathe children, or a caregiver is assisting someone with a bath, extra floor space will be needed to accommodate them as well as the user.
When planning for a free-standing tub, consider which side(s) of the tub will be used for entering, exiting and passage, and allow the proper clearances.
Grab bars placed in the tub will give users something to hold onto as they enter and exit, thus alleviating some balance problems. The NKBA recommends grab bars at the tub and shower to assist with this transfer. There are many decorative and attractive grab bars available to match other trim and accessories in the bathroom. It is critical that they be installed so they support at least 250 lbs. Some clients may need more support.
The wall behind the tub and shower should be reinforced to support the grab bar. The placement of the bar should be planned where it best fits the user.
Besides rails placed at the back and ends of the tub, a vertical bar at the front, and one on the back wall at a diagonal, are often helpful. Standard towel bars and soap dishes will not support someone in a fall and can be dangerous, since they protrude.
Tubs are most safely used if their floor is level with the bathroom floor, and the deck or top of the tub is approximately seat height (plus or minus 18 inches). Even one step into the tub creates a situation that can challenge balance and, therefore, is not recommended.
A tub sunk into the floor is even worse since it creates a situation where the user will step down from the floor level to the tub level. Or the person will need to sit on the floor to get into the tub, which is difficult for many. The sunken tub may also create a hazard if one were to trip and fall into it.
A tub placed on a high platform can require several steps to get up to, creating the same problem as the sunken tub. When users reach the top of the steps, they have to step down onto the bottom of the tub, more than 15 inches below them.
Even though it is clear that steps can cause a hazard, a client may insist on them. If you have to compromise, try to design so the step is strictly decorative and not actually used for tub entry. Use only one step designed in compliance with local building codes, or at least 10-in. deep and 71/4-in. high. A grab bar or handrail must be included for safety.
Faucet controls should be accessible to the user before entering the tub. In an enclosed tub or tub/shower combination, the controls may be placed on the wall at 33-in. above the finished floor. In general, off-setting the controls toward the room improves access by reducing bending and stretching.
Placing controls within 6 inches of the front wall makes them more accessible. For a free-standing tub, or one placed in a platform, controls should be on the front side. The user should not have to lean across the tub to turn on the water and check temperature. Place the faucet and controls so they do not conflict with the transfer area.
Besides faucet placement, the type and design should be considered. A faucet with a hand spray and 60-in. hose allows a caregiver to assist with bathing. Controls should be easy to grasp and manipulate. Any design other than smooth round knobs improves function. A single control is easier to use than separate hot and cold controls. If a tub/shower combination is planned, the shower controls must be pressure balanced, have thermostatic mixing, or be a combination of both.
Most prefabricated showers come in standard sizes from 32-in. to 48-in. square.
The recommended interior shower size for one person is at least 36-in. by 36-in. This allows one person to comfortably stand in the shower with arms raised to wash their hair. Building codes state that the minimum interior shower size is 30-in. by 30-in., but this is a tight space for most adults.
Check angled showers to make sure a 30-in. disc will fit into the shower floor. This will meet minimum code requirements. A larger disc area should be specified when user needs require more space.
For a person to move out of the shower spray inside the shower, a 42-in. by 36-in. shower should be considered. Larger prefabricated showers are available, and custom showers can be designed to meet the needs of the user. (Check that any prefabricated shower will fit through the bathroom door.) In a shower at least 60 inches deep, it is possible to control the spray within the shower. In a two-person shower, make sure there is room for both people.
Because most users stand in the shower, the risk of falling is great. Grab bars are recommended for the back and sides of the shower. A vertical bar at the shower entrance provides a helpful support when getting in and out. The surface and design of all grab bars should reduce the risk of a hand slipping on the bar.
The showerhead should be placed so it directs water toward the body, not the face or hair. A fixed showerhead, roughed in at 72-in. to 78-in. off the floor, is typical in many showers and tub/shower combinations. Plan the shower rough-in so that the bottom of the showerhead will be 72-in. off the finished floor or at a height appropriate to the user.
A showerhead on an adjustable bar, or a handheld showerhead, offers flexibility in a shower used by persons of different heights, or for different activities. When the adjustable height shower/hand spray is used, its lowest position should always be within the universal reach range (15 in. to 48 in. above finished floor).
The most convenient way for a plumber to install the shower control valves is to line them up under the showerhead.
However, this is not most convenient for the user. Being able to reach the controls while standing outside of the shower spray is ideal. The NKBA recommends that the controls be placed out of the water spray and between 38-in. to 48-in. above the floor. An accessible location is 6 inches from the outside of the fixture.
The books in the NKBA Professional Resource Library series are available only through the NKBA. To order, go to nkba.org or call 800-THE-NKBA.