Bathroom Codes and Design Best Practices

A modern-style bathroom

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It is too easy to look at bathroom codes as a set of onerous restrictions designed to squeeze your wallet dry.

While some parts of the bathroom building code may seem nitpicky, in many ways, it can be a useful guide as to what goes where and how to space all of the elements during your bathroom remodel.


  • Sinks should be spaced at least four inches from sidewalls.
  • Sinks should also have a minimum of 21 inches of clearance in front.
  • Do you want to put two sinks side by side? Make certain that they are at least four inches apart from one another.
  • Bathroom code typically mandates that sinks should be at least four inches from bathtubs.

Showers and Bathtubs

  • Are you looking to build a shower of any size? While shower maximum sizes are not mandated, minimums are. Shower floor minimum size is usually mandated to be at least 30 inches square; that is, 30 inches by 30 inches.
  • Because shower doors are usually glass and can break (and because of other access issues), bathroom code says that shower doors need to have at least 24 inches of opening clearance.
  • Both showers and bathtubs need anti-scald devices.
  • Some communities require water-saving showerheads that limit flow.


  • Bathroom building code typically says that toilets need at least 21 inches of clearance in front. Opting for 30 inches provides a more comfortable space, though.
  • Side to side clearance: a minimum of 15 inches from center-line of the toilet to the nearest obstruction. However, 18 inches provides better clearance in most cases.
  • Many communities require water-saving devices on the toilet.

Ventilation and Electrical Code and Design

Bathroom code as it relates to electricity is very important due to the possibility of shocks and fire.

  • All lights over bathtubs and showers are required to be vapor- and waterproof.
  • Outlets must be GFCI (ground fault current interrupter) outlets.
  • Bathroom code doesn't want you standing in tubs or showers while turning switches on or off, so switches must be 60 inches minimum from these places.
  • Bathrooms do not need to have fans, but they are required to have ventilation. This ventilation can be either in the form of a window at least three square feet in area or a bathroom fan capable of pulling out at least 50 cubic feet of air per minute.

Where Does Bathroom Code Come From?

Though based on the framework of model codes, bathroom code is not the same everywhere. Codes in Maine may not necessarily be the same as codes in Florida. Not only that, but municipalities can add their twists to the code to adapt to local needs.

Bathroom codes in this guide can point you in a general direction. Check with your permitting department to make sure that this code information applies to you.

This is not an exhaustive guide; these are only the most popular elements that most homeowners tend to be interested in.