Washington Building Code Height Limits By Construction Type

(g) The city or county may not establish roof height limits on an accessory dwelling unit of less than 24 feet, unless the height limitation that applies to the principal unit is less than 24 feet, in which case a city or county may not impose roof height limitation on accessory dwelling units that is less than the height limitation that applies to the principal unit; (h) A city or county may not impose setback requirements, yard coverage limits, tree retention mandates, restrictions on entry door locations, aesthetic requirements, or requirements for design review for accessory dwelling units that are more restrictive than those for principal units;