The basic requirement is at least one wall switched light should be installed in every habitable room, kitchen, and bathroom, according to the National Electrical Code [NEC 210.70(A)(1)]. In rooms other than kitchens and bathrooms, one or more receptacles controlled by a wall switch can substitute for a switched light

    But there are also several additional required locations for switched light fixtures (not switched receptacles), per NEC 210.70(A)(2):

** At least one switched light required in hallways, stairways, attached garages, and also detached garages that have electrical power.

•• At least one swtiched light must be installed at the exterior side of outdoor entrances to a dwelling unit, attached garage, and detached garage that has electric power. A vehicle door is not considered an outdoor entrance.

•• Interior stairways with six or more risers require lighting switched at the top and bottom landings (three-way switch). 

•• Any attic, underfloor space, utility room or basement that is used for storage or contains equipment that requires servicing, must have a minimum of one wall switched light.

•• Lights must not be controlled by a dimmer switches unless they provide a full range of dimming control at each location.

    And there are, of course, exceptions:

•• Lights are allowed to be controlled by occupancy sensors if they are either in addition to wall switches or equipped with a manual override switch.

•• At hallways, stairways, and outdoor entrances, remote, central, or automatic controll of lighting shall be permitted.

    Also, see our blog posts How can I figure out what a mystery wall switch does? and Why does the bedroom have a light switch but there is no light in the ceiling? 

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Here’s links to a collection of our other blog posts about ELECTRICAL WIRING:

• What is the color code for NM cable (Romex®) sheathing?

• Why are old electrical components not always "grandfathered" as acceptable by home inspectors?

• How can I find out the size of the electric service to a house?

• Can old electrical wiring go bad inside a wall? 

• What is an open electrical splice?

• What are the most common electrical defects found in a home inspection? 

• What is the life expectancy of electrical wiring in a house? 

• What is an "open junction box"? 

• How dangerous is old electrical wiring? 

• What is a ground wire? 

• I heard that aluminum wiring is bad. How do you check for aluminum wiring?  

• What is "knob and tube" wiring?  

• What is the code requirement for receptacle outlets in a closet?

   Visit our ELECTRICAL page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.