Because the combination of water and electricity can be deadly, code requirements for bathrooms are strict. They're designed to protect your family from injury or death as the result of electrocution. The National Electric Code (NEC) determines which items in a bathroom can be on the same electrical branch circuit.
If the branch circuit you're working with only supplies electricity to a single bathroom and not to any other part of your home, then the outlets in the bathroom and the lights can be on the same circuit. You can also run the room’s exhaust fan on the same circuit. While this is acceptable under NEC guidelines, you can run into trouble if something trips the GFCI receptacle in the bathroom. Not only will you lose the use of the outlet, but the lights and fan may also shut off.
If you need to run power to multiple bathrooms in your home, the code requirements change. You may use the same branch circuit to supply power to the outlets in more than one bathroom, but you cannot place lights or other items on that same circuit. It doesn’t matter if the lights are in bathrooms or other parts of the home; the circuit must be dedicated to the bathroom outlets. A second circuit can serve lights and exhaust fans in the bathrooms.
According to the NEC, at least one outlet is required in a bathroom and it must be within 3 feet of the outside edge of the sink. You cannot place an outlet inside or above a shower or bathtub. The outlets in the bathroom and the branch circuit that supplies power to the room should be rated at 20 amperes. The outlets must have GFCI protection. GFCI, or Ground-Fault Circuit Interrupters, cut power to the outlet to prevent electrocution.
While the NEC is accepted throughout the United States, your local municipality may have other requirements for electricity in bathrooms. Before making changes to your home’s bathroom, consult with a local building inspector. She can let you know if your plans violate any code requirements and save you from having to make expensive repairs when you try to sell your home in the future.
- Residential Wiring; H. Brooke Stauffer and Paul Rosenberg