Published on Feb 18, 2019

Another set of ADU bills

Contact: Carl Schroeder, Shannon McClelland

A pair of particularly restrictive accessory dwelling unit (ADU) bills are up for hearings. HB 5812, sponsored by Guy Palumbo (D–Maltby), just had a public hearing during the snow days. Its companion, HB 1797, sponsored by Mia Gregerson (D–SeaTac), is scheduled for a hearing and a committee vote this week.

These bills, by July 1 2020, require any city with a population of 2,500 or more and any county with a population of 15,000 or more to adopt by ordinance and incorporate into its development and zoning regulations an authorization for creating ADUs within designated Urban Growth Areas (UGAs).

Local ordinances and regulations must allow:

  • either one attached ADU and one detached ADU or two attached ADUs on all lots zoned for single-family homes and all lots that contain a single-family housing unit;
  • one attached ADU on any lot zoned for single-family homes; and
  • detached ADUs to be sited at the lot line of the rear yard if adjacent to an alley within five feet of the rear yard lot line if approved in writing by the adjacent property owner.

However, such ordinances and regulations must not:

  • impose minimum lot size requirements for siting ADUs;
  • require installation of new or separate utilities between an attached ADU and a utility;
  • consider attached ADUs to be new residential uses for calculating utility connection or capacity fees, but may require a utility connection between a detached ADU and a utility with the appropriate and proportionate connection or capacity fee;
  • prohibit the sale of a condominium unit on sole grounds it was originally an ADU;
  • count ADU residents towards the number of unrelated residents on a single-family lot;
  • establish requirements for ADU off-street parking;
  • require the lot owner to reside or occupy the ADU or other housing unit on the same lot;
  • count the gross floor area of an ADU against any single-family home floor area ratio limitations;
  • establish development standards that include certain roof and wall height limitations on detached ADUs;
  • regulate the location of ADU entry doors;
  • establish maximum rear yard coverages for detached ADUs less than 60 percent of the rear yard;
  • establish tree retention requirements for ADUs in addition to those that exist for single-family homes;
  • require the exterior design or appearance of an ADU be similar to the appearance of the principal housing unit;
  • limit the roof height of detached ADUs to less than 24 feet or limit their wall height to less than 17 feet; or
  • limit the maximum gross floor area of an ADU to less than 1,000 square feet or its minimum gross floor area to more than 140 square feet.

AWC opposes this heavy-handed, one-size-fits-all approach to encouraging more ADUs. We’ve heard from cities that ADUs have been welcomed in their committee because they have designed their ordinances in a way that enables ADUs to be an accepted and complimentary part of their community.


Dates to remember

HB 1797 is set for a hearing on Tuesday, February 19 at 10 am in the House Local Government Committee. The bill is also scheduled for a committee vote on Friday.

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