Sumner City Council relaxes rules on ADUs

At its August 15 meeting, Sumner City Council unanimously approved changes to the city code regarding accessory dwelling units. City code previously only allowed ADUs on lots of 12,000 square feet or more. The changes adopted lower that number to as low as 4,000 square feet if the ADU is attached to the main unit, and 6,000 square feet if the unit is a detached ADU (DADU), in low-density residential areas.

Other changes to code include increasing the ADU height limit to 18 feet to allow for more garage conversions to ADUs.

These changes follow upon action taken by the City in July which expanded the city’s multifamily tax exemption program for new development where 20 percent of the total units built are designated as affordable housing.