Restrooms in public and commercial buildings must include a specific set of fixtures, features, and design elements dictated by federal workplace rules, accessibility law, building codes, and ventilation standards. The exact requirements depend on whether the restroom serves employees, the public, or both, but the core elements are consistent: toilets in sufficient quantity, handwashing stations, grab bars, adequate ventilation, privacy partitions, and accessible design for people with disabilities.
Toilets and Minimum Fixture Counts
Every restroom needs at least one functioning toilet, but the number required scales with how many people use the space. OSHA requires employers to provide a minimum number of toilet facilities based on workforce size, in separate rooms for each sex. The goal is to prevent long lines and ensure prompt access whenever an employee needs it. Businesses open to the public face similar ratio requirements under local plumbing codes, which typically follow the International Plumbing Code or Uniform Plumbing Code and set fixture counts based on building occupancy type and expected foot traffic.
Handwashing Stations and Hygiene Supplies
A restroom without a way to wash hands does not meet any code. At minimum, each restroom must have a sink with running water, soap, and a hand-drying method (paper towels, air dryers, or both). OSHA mandates these for all workplace restrooms. The CDC identifies faucet handles, sink edges, and door handles as high-touch surfaces that harbor pathogens, which is why many current building codes and health departments encourage or require touchless faucets, soap dispensers, and paper towel dispensers in high-traffic public restrooms.
Toilet paper dispensers are required in every stall. Waste receptacles are also standard requirements, with many jurisdictions specifically requiring them in women’s restrooms for sanitary product disposal.
ADA Accessibility Requirements
The Americans with Disabilities Act sets detailed, measurable standards for restroom design. These are not suggestions. Any restroom in a place of public accommodation or a workplace must comply.
The room itself needs enough space for a wheelchair to maneuver: a turning area at least 60 inches in diameter (or a T-shaped turning space). Toilet seats must be mounted 17 to 19 inches high, measured to the top of the seat. The toilet centerline must sit 16 to 18 inches from the side wall.
Grab bars are required on both the side wall and rear wall next to the toilet. The side grab bar must be at least 42 inches long, positioned 12 inches from the rear wall. The rear grab bar must be at least 36 inches long, extending 12 inches past the toilet centerline. Both must be mounted with exactly 1.5 inches of clearance between the bar and the wall (this is a fixed dimension, not a minimum, to prevent arm or hand entrapment). Every grab bar, along with its fastener and mounting hardware, must support 250 pounds of force applied vertically or horizontally at any point.
Sinks need a clear floor space of at least 30 inches wide for a forward wheelchair approach. If partitions block both sides of that space for more than 24 inches, the clearance widens to 36 inches. In a multi-stall restroom, at least one stall must be fully ADA-compliant with a minimum width of 60 inches, proper turning space, and a door that swings outward unless interior clearances allow an inward swing without restricting movement.
Privacy Partitions and Stall Design
Every toilet in a multi-user restroom must be enclosed by partitions and a door that provides visual privacy. Stalls must meet minimum width and depth requirements set by building codes, and doors need functioning latch hardware that can be operated with one hand and without tight grasping or twisting (an ADA requirement that applies to accessible stalls but is good practice everywhere). Partition heights must be tall enough to provide appropriate privacy while leaving a gap at the bottom for cleaning access and emergency visibility, typically 12 to 14 inches off the floor depending on local code.
Ventilation and Air Quality
Restrooms produce odors and moisture that breed mold and bacteria, so mechanical exhaust ventilation is required by building codes. ASHRAE Standard 62.1, the benchmark adopted by most jurisdictions, sets specific airflow rates based on restroom type. A private single-user toilet requires 25 cubic feet per minute (CFM) of continuous exhaust, or 50 CFM if the fan runs intermittently (such as on a motion sensor or timer). Public restrooms with multiple fixtures need 50 CFM per fixture for continuous operation, or 70 CFM per fixture for intermittent systems. These rates ensure that contaminated air is pulled out and replaced with fresh air frequently enough to maintain acceptable indoor air quality.
Baby Changing Facilities
Federal law now requires baby changing stations in many public buildings. The Bathrooms Accessible in Every Situation Act (BABIES Act) mandates that restrooms in buildings controlled by the General Services Administration be equipped with changing tables or similar devices suitable for children age 3 and under. These must be physically safe, sanitary, and appropriate. Exceptions exist for restrooms not open to public use, buildings where the construction cost would be unfeasible, and restrooms on a floor where another restroom with a changing table is available (as long as clear signage directs users to it). Many state and local codes extend similar requirements to private commercial buildings like restaurants and retail stores, and increasingly require changing stations in both men’s and women’s restrooms.
Flooring, Walls, and Surface Materials
Health codes and building codes require restroom surfaces to be smooth, nonabsorbent, and easy to clean. Floors must be slip-resistant even when wet, which is why ceramic tile, porcelain, and sealed concrete are standard choices. Porous materials like unsealed wood or carpet are not acceptable for restroom floors in commercial settings because they absorb moisture and harbor bacteria. Walls adjacent to sinks, urinals, and toilets typically need to be finished with washable, moisture-resistant materials to a height of at least 48 to 72 inches, depending on the jurisdiction. Coved base flooring (where the floor material curves slightly up the wall) is commonly required to eliminate the seam where floors meet walls, a spot that otherwise traps moisture and grime.
Lighting and Signage
Building codes require restrooms to have adequate artificial lighting, typically a minimum of 10 to 20 foot-candles depending on the code. Restroom entrances must display signage identifying the room’s purpose. ADA-compliant signage includes raised characters and Braille, mounted on the latch side of the door at a specific height so that visually impaired users can locate and read them by touch. If a restroom is accessible, the International Symbol of Accessibility must be displayed.
Hot Water and Plumbing Standards
Handwashing sinks must supply water at a temperature that facilitates effective hand cleaning. Most plumbing codes require tempered water at sinks in public restrooms, meaning the maximum outlet temperature is capped (commonly at 110°F) to prevent scalding. Every fixture must connect to an approved drainage system, and backflow prevention devices are required to keep contaminated water from entering the clean supply. Floor drains are required in most commercial restrooms to handle overflow and simplify mopping.