Benefits of a one-piece bathtub and shower include a seamless construction that is highly durable. The tub-and-shower combination also is a good choice where limited space does not allow for a separate tub and shower.
The seamless construction of the one-piece unit provides protection from leaks that cause deterioration of the walls behind the tub. These acrylic or fiberglass units help to prevent the growth of mildew and mold in the bathroom and behind the tub enclosure. By adding sliding glass doors instead of a shower curtain, owners can increase the illusion of space in very small bathrooms.
The single-piece unit works best with new construction. The contractor sets the unit in the bathroom area before erecting all the stud walls. Because of its size, it is difficult to maneuver into most existing bathrooms, making it impractical for most bathroom remodels, where multiple piece shower-tub combinations are easier to install.
Manufacturers are working to increase options such as grab bars and imprint a pattern on some units to resemble tile. However, as of 2015, consumers still find the color choices and styles of these units more limited than with other types of tub-shower combinations.
Tub-shower combinations also require the user to step over the side of the tub to use it. In applications where the user has limited mobility, a separate shower provides a better option than a combination unit.