Exterior Lighting Standards in Washington State

Efficiency

• The state of Washington requires homeowners to use high-efficiency light bulbs in many outdoor lighting fixtures. Luminaires that function at more than 100 watts must contain light bulbs with an efficacy rating of at least 60 lumens per watt, with lumens determining how much light the bulbs produce for each watt of energy they consume. Outside the home, Washington law allows 1 watt of electricity per square foot for each fixture.

Efficiency Exceptions

• Washington makes exceptions to its efficiency rules for some exterior fixtures. Temporary lighting and lights associated with transportation, including street and address signs, can fall outside the 60-lumen rule. Lawmakers exempted any lighting integral to outdoor equipment from the rules as well. Lighting that illuminates exterior stairways, driveways, swimming pools or sidewalks can also feature brighter lighting, though regulations apply based on the width the stairs or pathways. Sidewalks greater than 10 feet wide, as well as any stairs, enjoy more lenient lighting rules.

Local rules

• In addition to state laws, many cities and counties in Washington maintain their own outdoor-lighting codes. In some towns, regulations prohibit installation of unshielded floodlights and drop-lens lights with exposed bulbs, and instead encourage downward-directed, flush-mounted and fully shielded lamps. Other local rules limit the amount of outdoor light that can travel from your yard onto your neighbor's property. The city of Seattle has explicit light and glare standards applying to single-family residential areas, as well as midrise and high-rise living environments. Homeowners interested in outdoor lighting rules should check local ordinances as well as state laws.

Exemptions

• Washington law exempts some lighting sources from all state and local rules regarding not just efficacy, or lumens per watt, but also placement and shielding. Lamps that illuminate areas routinely used by the visually impaired doesn't fall under lighting codes. And because the hard of hearing must read lips, lighting in outdoor spaces frequented by the deaf also rests outside the codes. Emergency lighting that is automatically off during normal home operation is exempt as well.