Bathrooms and Layouts in Residential Bathroom Design

When it comes to designing residential bathrooms, there are several factors to consider. The International Residential Code provides guidelines for spatial requirements, including minimum fixture clearances and wall materials for bathtubs and shower spaces. Additionally, other sections of the code address plumbing, mechanical, and electrical issues in bathrooms.

One important aspect of bathroom design is the selection of accessories. Typical accessories include a medicine cabinet, mirror, soap dish, toilet paper holder, towel bar, and linen storage space. It is recommended to allow between 24 and 36 inches of towel bar space for each family member using the bathroom.

Fixture Sizes and Clearances

Understanding fixture sizes and clearances is essential for effective bathroom design. Here are some minimum and liberal measurements for common fixtures:

• Water closet (toilet):

  • Minimum A: 27"
  • Liberal A: 31"
  • Minimum B: 19"
  • Liberal B: 21"
  • Minimum C: 15"*
  • Liberal C: 18"
  • Minimum D: 15"*
  • Liberal D: 22"
  • Minimum E: 21"*
  • Liberal E: 36"

• Bidet:

  • Minimum A: 25"
  • Liberal A: 27"
  • Minimum B: 14"
  • Liberal B: 14"
  • Minimum C: 15"*
  • Liberal C: 18"
  • Minimum D: 15"*
  • Liberal D: 22"
  • Minimum E: 21"*
  • Liberal E: 36"

• Lavatory (sink):

  • Minimum A: 16"
  • Liberal A: 21"
  • Minimum B: 18"
  • Liberal B: 30"
  • Minimum C: 2"
  • Liberal C: 6"
  • Minimum D: 14"*
  • Liberal D: 22"
  • Minimum E: 21"*
  • Liberal E: 30"

• Shower (interior dimension):

  • Minimum A: 30"*
  • Liberal A: 36"
  • Minimum B: 30"*
  • Liberal B: 36"
  • Minimum C: 2"
  • Liberal C: 8"
  • Minimum D: 24"*
  • Liberal D: 34"
  • N/A
  • N/A

• Bathtub:

  • 60" standard
  • Liberal A: 72"
  • 30" standard
  • Liberal B: 48"
  • Minimum C: 21"
  • Liberal C: 34"

  • ---

  • *Designates code requirement
  • **Designates "As required by other fixtures"

Built-In Bathtub

Residential Bathroom Design Basics

When planning the layout and function of residential bathrooms, it is crucial to consider the overall bathroom layout. The primary components of any residential bathroom include bathtubs and showers, plumbing fixtures, and toilet, bath, and laundry accessories.

Bathtubs

Bathtubs come in various shapes, sizes, and styles, such as rectangular, corner, and oval. They can be installed in different ways, including recessed, drop-in, and freestanding installations. Common materials for bathtub surrounds include ceramic tile, solid surfacing, molded fiberglass, and acrylic one-piece units.

Typical Site-Built Shower Construction

Showers

Showers can be standalone fixtures or combined with bathtubs. When combined, they usually share a water supply valve. Shower enclosures are typically three-sided, with water-resistant walls and a shower door or curtain to complete the enclosure.

Plumbing Fixtures

Plumbing fixtures, such as faucets, sinks, toilets, and bidets, are designed to supply water or receive waterborne waste. It is important to choose fixtures made of nonabsorbent, nonporous, nonoxidizing, smooth, and easy-to-clean materials. Plumbing codes specify the number and type of fixtures required based on occupancy and also include provisions for people with disabilities.

Typical Water Supply and Drainage from a Plumbing Fixture

Bathroom Accessories

Bathroom accessories play a crucial role in both functionality and aesthetics. Here are some key accessories to consider:

• Medicine Cabinets: Available in surface-mounted or recessed styles, with left or right-hand door swings. Side-access cabinets eliminate the need to reach over a counter.

• Mirrors: The bottom edge of mirrors above lavatories, sinks, and vanities should be mounted a maximum of 40 inches above the floor. Full-length mirrors accommodate all users, including children and wheelchair users.

• Soap Dishes: Available in recessed and surface-mounted styles. For accessible purposes, soap dispensers should be mounted no more than 42 inches above the finished floor.

• Toilet Paper Holders: The location and operation of flush controls and toilet paper dispensers are regulated by standards. Manually operated flush controls must be located on the open side of the toilet, and the toilet paper dispenser should be within the allowable range.

• Towel Bars: Residential bathrooms typically have two towel bar locations, one near the sink and another near the tub and/or shower. Each family member using the bathroom should have between 24 and 36 inches of towel bar space.

• Linen Storage Spaces: There are various options for residential bathroom storage. Stainless steel shelves, full-extension drawer glides, and pullout drawer storage can enhance accessibility and storage capacity.

Water Closets

Further Reading on Residential Bathroom Design

If you're an architect looking for quick access to potential layouts and design practices, Architectural Graphic Standards (AGS) is an excellent resource to consider. AGS Online offers downloadable graphic illustrations for bathrooms and layouts, helping you create functional and visually appealing residential bathrooms.

Designing a residential bathroom involves careful consideration of spatial requirements, fixture clearances, and the selection of accessories. By following code requirements and considering user needs, you can create a bathroom that combines functionality and aesthetics seamlessly.