23.40.080

A. For the purposes of this Section 23.40.080 , "conversion to residential use in an existing structure" means a development that meets all the following criteria: 1. It does not expand a structure horizontally beyond the boundaries of the existing or approved exterior walls except for addition of incidental features that are necessary to accommodate residential use such as: ramps for ADA access, replacement windows or sheathing, addition of material enabling increased insulation, structural features to increase safety, additions for the purpose of complying with construction and energy codes and building performance standards for the conversion to residential use, circulation features for fire and life safety, mechanical equipment, plumbing and duct work, or awnings and bays. The horizontal expansion for incidental features shall not increase the floor area of the structure by more than 5 percent. 2. It does not expand the structure vertically beyond the existing or approved roof elevation, except by up to 15 feet to accommodate configuration or expansion of top floor residential use or rooftop features in residential use. Stair and elevator penthouses, mechanical equipment, and rooftop features allowances otherwise provided by the underlying zone may be placed on top of the 15-foot accommodation for configuration of top floor residential use without disqualifying the development from meeting this criterion. 3. The building in which the conversion would occur received either a temporary or permanent certificate of occupancy prior to March 1, 2024, or if no temporary or permanent certificate of occupancy is available is determined by the Director to have been legally occupied or is in a building approved for future development for which an unexpired Master Use Permit was issued, prior to March 1, 2024. 4. It is a conversion of floor area from nonresidential uses to residential uses that increases the number of dwelling units or congregate residence sleeping rooms in the structure. 5. It does not increase the square footage of nonresidential uses in the structure. 6. It is located in a commercial zone, a Downtown zone, a Seattle Mixed (SM) zone, the Highrise (HR) zone, or the Midrise (MR) zone. B. The determination of whether a proposed development qualifies as a conversion to residential use in an existing structure pursuant to subsection 23.40.080.A, and any related land use approvals concerning how the standards of this Section 23.40.080 apply shall be Type I decisions. C. A conversion to residential use in an existing structure meeting the criteria of subsection 23.40.080.A shall be exempt from all development standards and land use regulations of Chapter 23.45 (Multifamily), Chapter 23.47A (Commercial), Chapter 23.48 (Seattle Mixed), Chapter 23.49 (Downtown Zoning), Chapter 23.52 (Transportation Concurrency, and Transportation Impact Mitigation), Chapter 23.53 (Requirements for Streets, Alleys, and Easements), Chapter 23.54 (Quantity and Design Standards for Access, Off-Street Parking, and Solid Waste Storage), and Chapter 23.58A (Incentive Provisions), except that the following categories of development standards and regulations within any of those chapters shall continue to apply: 1. Permitted and prohibited use regulations pertaining to nonresidential uses; 2. Administrative conditional use regulations; 3. Light and glare standards; 4. Noise standards; 5. Institutions; 6. Home occupations; 7. Transitional encampment accessory uses; 8. Landmark Districts and designated landmark structures; and 9. Subsections 23.54.040.F, 23.54.040.G, 23.54.040.H, 23.54.040.I, and 23.54.040.J, solid waste and recyclable material storage and access. D. A development proposal for conversion to residential use in an existing structure meeting the criteria of subsection 23.40.080.A in a building with features that are legally nonconforming to applicable development regulations for nonresidential use shall retain a comparable legal nonconforming status upon conversion to residential use. The Director may approve as a Type I decision any additional features of an existing building nonconforming to applicable development regulations which in the judgment of the Director cannot reasonably be rendered conforming in connection with conversion to residential use. E. A conversion to residential use in an existing structure meeting the criteria of subsection 23.40.080.A shall be exempt from design review if the structure is already constructed or construction has commenced on the structural frame for the structure. F. A conversion to residential use in an existing structure meeting the criteria of subsection 23.40.080.A.1-5 and located in a commercial zone, Downtown zone, or a Seattle (SM) Mixed zone shall be exempt from requirements under Chapter 23.58C (Mandatory Housing Affordability for Residential Development) for any portion of the development proposal that converts floor area from a nonresidential use to a residential use. G. A conversion to residential use in an existing structure meeting the criteria of subsection 23.40.080.A shall be subject to the following if the conversion is in a building approved for future development for which an unexpired Master Use Permit was issued prior to March 1, 2024, and construction on the structural frame for the structure has not yet commenced: 1. Any design review modification to the issued and unexpired Master Use Permit necessary to add residential use shall be reviewed, and may be approved by the Director as a Type I decision; and 2. Notwithstanding the provisions of subsection 23.58C.025.B, any portion of the development proposal that converts floor area from a nonresidential use to a residential use shall be subject to the requirements of Chapter 23.58C that were in effect on the vested date of the unexpired Master Use Permit. H. An applicant for a conversion to residential use in an existing structure meeting the criteria of subsection 23.40.080.A that vested to this Chapter 23.40 prior to August 12, 2024, may elect to modify the vesting date of the development pursuant to subsection 23.76.026.F to a date subsequent to August 12, 2024. (Ord. 127228 , § 4, 2025; Ord. 127054 , § 1, 2024.)