Mitigation of impacts—Performance option
Seattle Mun. Code § 23.58B.050
in effectA. Performance option 1. An applicant complying with this Chapter 23.58B through the performance option shall provide total net unit area, measured according to subsection 23.86.007.B, of MHA-C units meeting the standards of subsection 23.58B.050.B, equal to at least the percentage calculation amount per square foot according to Table A or Table B for 23.58B.050 and Map A for 23.58B.050, as applicable, multiplied by the total square feet of chargeable floor area in commercial use, or gross floor area in commercial use that is not underground if there is no FAR limit in the underlying zone, as follows: a. Including chargeable floor area in commercial use in the following: 1) A new structure; 2) An addition to a structure; 3) A change of use from residential use to commercial use; or 4) Any combination of the above; and b. Excluding chargeable floor area in commercial use as follows: 1) The first 4,000 gross square feet of street-level commercial uses; and 2) Street-level commercial uses along a designated principal pedestrian street in a Pedestrian designated zone. 2. If the calculation according to subsection 23.58B.050.A.1 yields fewer than three MHA-C units using a conversion factor for unit size as determined by the Director, the applicant shall either round up to three units or provide a cash contribution using the payment option according to subsection 23.58B.040.A. Table A for 23.58B.050 Performance calculation amounts: In Downtown, SM-SLU, SM-U, and SM-NG zones Zone Performance calculation amount per square foot DH1/45 Not applicable DH2/55 Not applicable DH2/75 9.1% DH2/85 Not applicable DMC 75 5.0% DMC 95 5.0% DMC 85/75-170 5.0% DMC 145 6.1% DMC 170 5.0% DMC 240/290-440 6.1% DMC 340/290-440 7.6% DOC1 U/450-U 8.9% DOC2 500/300-550 8.6% DRC 85-170 8.2% DMR/C 75/75-95 5.0% DMR/C 75/75-170 5.0% DMR/C 95/75 10.6% DMR/C 145/75 10.6% DMR/C 280/125 8.7% DMR/R 95/65 8.5% DMR/R 145/65 9.7% DMR/R 280/65 9.7% IDM 65-150 Not applicable IDM 75-85 Not applicable IDM 85/85-170 5.0% IDM 165/85-170 7.0% IDR 45/125-270 5.0% IDR 170 5.0% IDR/C 125/150-270 7.0% PMM-85 Not applicable All PSM zones Not applicable SM-NG 145 6.0% SM-NG 240 9.0% SM-SLU 100/65-145 5.0% SM-SLU 85/65-160 Not applicable SM-SLU 85-280 5.0% SM-SLU 175/85-280 6.8% SM-SLU 240/125-440 6.1% SM-SLU/R 65/95 5.0% SM-SLU 100/95 5.0% SM-SLU 145 5.6% SM-U 85 5.0% SM-U/R 75-240 9.0% SM-U 75-240 9.0% SM-U 95-320 9.0% Table B for 23.58B.050 Performance calculation amounts: Outside Downtown, SM-SLU, SM-U, and SM-NG zones Zone Performance calculation amount per square foot Low Medium High All Industrial Buffer zones (IB) Not applicable Not applicable Not applicable All Industrial General zones (IG) Not applicable Not applicable Not applicable All Maritime, Manufacturing, and Logistics zones (MML) Not applicable Not applicable Not applicable All Urban Industrial zones (UI) Not applicable Not applicable Not applicable All Master Planned Communities—Yesler Terrace zones (MPC-YT) Not applicable Not applicable Not applicable II 85-240 6.1% 6.1% 6.1% All other II zones Not applicable Not applicable Not applicable Zones with an (M) suffix 5.0% 5.0% 5.0% Zones with an (M1) suffix 8.0% 8.0% 8.0% Zones with an (M2) suffix 9.0% 9.0% 9.0% Other zones where provisions refer to Chapter 23.58B 5.0% 5.0% 5.0% Map A for 23.58B.050 Payment and performance areas: high, medium, and low B. General performance standards. All MHA-C units shall meet the following standards: 1. Duration. The obligation to provide MHA-C units shall be for a minimum period of 75 years from the date of issuance of the certificate of occupancy, or if a certificate of occupancy is not required, from the date of the final building permit inspection, for the MHA-C units; provided that, in the case of demolition of a structure containing both MHA-C units provided according to this Section 23.58B.050 and units provided to comply with Chapter 23.58C through the performance option according to Section 23.58C.050 , the obligation to provide MHA-C units shall last no longer than the time specified according to subsection 23.58C.050.B.1.b.1. 2. Tenure. MHA-C units shall be rental housing for eligible households according to subsection 23.58B.050.B.6. 3. Rent limits. Monthly rent for MHA-C units shall not exceed 30 percent of 60 percent of median income or, in the case of any unit with net unit area of 400 square feet or less, 30 percent of 40 percent of median income. For purposes of this subsection 23.58B.050.B.3, "monthly rent" includes a utility allowance for heat, gas, electricity, water, sewer, and refuse collection, to the extent such items are not paid for tenants by the owner, and also includes any recurring fees that are required as a condition of tenancy. 4. Type. MHA-C units shall be dwelling units, except for accessory dwelling units or detached accessory dwelling units. 5. Comparability. MHA-C units shall be comparable to the other dwelling units to be developed in terms of the following: a. Number and size of bedrooms and bathrooms; b. Net unit area measured as square feet; c. Access to amenity areas; d. Functionality; and e. Term of the lease. 6. Eligible households. MHA-C units shall serve only: a. At initial occupancy by a household: 1) For a unit with net unit area of 400 square feet or less, households with incomes no higher than 40 percent of median income; or 2) For a unit with net unit area of greater than 400 square feet, households with incomes no higher than 60 percent of median income. b. At the time of annual certification according to subsection 23.58B.050.B.13: 1) For a unit with net unit area of 400 square feet or less, households with incomes no greater than 60 percent of median income; 2) For a unit with net unit area of greater than 400 square feet, households with incomes no greater than 80 percent of median income. 7. Affordable housing; no other restrictions. MHA-C units and restricted units provided for any other reason, including a property tax exemption or loans and grants, must be different units. 8. Time of completion. Except as provided according to subsection 23.58B.050.C.4, MHA-C units shall be completed and ready for occupancy at or before the time when a final certificate of occupancy is issued for the development mitigating impacts according to this Chapter 23.58B , and shall be a condition to any right of the applicant to such certificate of occupancy. 9. Age of construction; distribution. MHA-C units shall be newly constructed and shall be generally distributed throughout the residential portion of the development. 10. Affirmative marketing. MHA-C units shall be affirmatively marketed to attract eligible households from all racial, ethnic, and gender groups in the housing market area of the property, particularly to inform and solicit applications from households who are otherwise unlikely to apply for housing in the development. Proposed marketing efforts shall be submitted to the Office of Housing for review and approval. Records documenting affirmative marketing efforts shall be maintained and submitted to the Office of Housing upon request. 11. Reporting. Periodically as may be required by the Director of Housing, but no less than annually, the owner of the MHA-C units shall submit to the Office of Housing a written report demonstrating compliance with and housing outcomes of this Chapter 23.58B . The report shall include required information and supporting documentation, verified upon the owner's oath or affirmation and in a form prescribed by the Office of Housing. The Director of Housing is authorized to assess a late fee of $50 per day, which shall accrue until the report is submitted, starting 14 days from the date of the Office of Housing's notice that the report is overdue. 12. Limitation on charges. Fees charged to eligible households upon move-in or transfer within a development containing MHA-C units shall be limited to a reasonable level to be established by the Director of Housing by rule. No tenant of a rental unit may be charged fees for income verifications or reporting requirements related to this Chapter 23.58B . 13. Annual certification, third party verification a. The owner of the structure(s) that includes the MHA-C units shall obtain from each tenant, no less than annually, a certification of household size and annual income in a form acceptable to the Director of Housing. The owner shall examine the income of each tenant household according to 24 CFR 5.609, with guidance from the HUD Occupancy Handbook 4350.3, Chapter 5. The owner also shall examine the income and household size of any tenant at any time when there is evidence that the tenant's written statement was not complete or accurate. If so requested by the City, the owner shall obtain such certifications and/or examine incomes and household sizes at any other times upon reasonable advance notice from the City. The owner shall maintain all certifications and documentation obtained according to this subsection 23.58B.050.B.13 on file for at least six years after they are obtained, and shall make them available to the City for inspection and copying promptly upon request. b. The owner of the structure that includes the MHA-C units shall attempt to obtain third party verification whenever possible to substantiate income at each certification, which shall include contacting the individual income source(s) supplied by the household. The verification documents shall be supplied directly to the independent source by the owner and returned directly to the owner from the independent source. In the event that the independent source does not respond to the owner's faxed, mailed, or emailed request for information, the owner may pursue oral third party verification. If written or oral third party documentation is not available, the owner may accept original documents (pay stubs, W-2, etc.) at the discretion of the Director of Housing and shall document why third party verification was not available. At the discretion of the Director of Housing, the owner may accept tenant self-certifications after the initial income verification and first annual recertification. 14. Annual fee. The owner of the structure that includes the MHA-C units shall pay the Office of Housing an annual fee of $190 per MHA-C unit for the purpose of monitoring compliance with the requirements of to this Section 23.58B.050 . The annual fee shall automatically adjust annually on March 1, starting in 2024, by an amount in proportion to the increase, if any, for January 1 through December 31 of the prior calendar year, in the Consumer Price Index, All Urban Consumers, Seattle-Tacoma-Bellevue, WA, All Items (1982-84=100), as determined by the U.S. Department of Labor, Bureau of Labor Statistics or successor index, unless the Director of Housing makes a determination that a lower fee covers the cost of monitoring compliance. 15. Over-income households; unit substitution. If, based on any certification, a previously eligible household occupying an MHA-C unit is determined to be ineligible due to exceeding the income limits according to subsection 23.58B.050.B.6, the owner of the development containing the MHA-C units shall, through the process according to subsection 23.58B.025.A.5, designate a comparable substitute MHA-C unit within the development, as approved by the Director of Housing, as soon as such a unit becomes available, and upon such designation the requirements of this subsection 23.58B.050.B and subsection 23.58B.050.C shall transfer to the substitute unit. All of the rental units in the development that contains the MHA-C units shall be considered as potential substitute replacement units. Upon such determination that a previously eligible household is ineligible, the owner shall promptly give the ineligible household notice of such determination and notice that the requirements of this subsection 23.58B.050.B and subsection 23.58B.050.C shall transfer to a substitute MHA-C unit when such unit becomes available. Upon the transfer of the requirements, the owner shall give the ineligible household six months' notice prior to any rent increase. 16. Maintenance, insurance. MHA-C units, and the development in which the MHA-C units are located, shall be maintained by the owner in decent and habitable condition, including the provision of adequate basic appliances. The owner shall keep the MHA-C units, and the development in which the MHA-C units are located, insured by an insurance company licensed to do business in the state of Washington and reasonably acceptable to the City, against loss by fire and other hazards included with broad form coverage, in the amount of 100 percent of the replacement value. 17. Agreement. The City and the owner of the structure(s) that include the MHA-C units shall enter into an agreement specifying the requirements of this Section 23.58B.050 . The agreement shall be recorded on the title of the property on which the MHA-C units are located. The requirements specified in the agreement shall be consistent with final plans for the MHA-C units. If the first building permit is issued for the structural frame for the structure that includes affordable housing according to this Chapter 23.58B and such structure is acquired to provide City-funded low-income housing, the agreement according to this subsection 23.58B.050.B.17 may be released at the sole discretion of the Director of Housing. 18. Casualty a. If an MHA-C unit is destroyed or rendered unfit for occupancy by casualty, the owner of the MHA-C unit shall, through the process according to subsection 23.58B.025.A.5, designate a comparable substitute MHA-C unit within the development, as approved by the Director of Housing, as soon as such unit becomes available, which the tenant household of the MHA-C unit affected by casualty shall be allowed to move into, and upon such designation the requirements of subsection 23.58B.050.B shall transfer to the substitute unit. b. If any casualty loss results in the loss of one or more MHA-C units for a period of one year or more, the duration according to subsection 23.58B.050.B.1.a shall be automatically extended beyond the original term hereof for a period equal to the period of time for which the MHA-C units are not in service and no comparable MHA-C units have been provided and placed in service within the development. C. Additional performance standards. In addition to meeting the standards in subsection 23.58B.050.B, MHA-C units located on a site other than the same lot as the development required to mitigate affordable housing impacts according to this Chapter 23.58B shall meet the following additional standards: 1. Equal or better mitigation. The applicant shall demonstrate to the satisfaction of the Director of Housing that affordable housing impact mitigation provided through the performance option on a site other than the same lot as the development required to mitigate affordable housing impacts according to this Chapter 23.58B is equal to or better than mitigation provided through performance on the same lot. 2. Location. MHA-C units provided on a site other than the same lot as the development required to mitigate affordable housing impacts according to this Chapter 23.58B shall be located: a. Within the same regional center or urban center as the development required to mitigate affordable housing impacts according to this Chapter 23.58B ; or b. Within one mile of the development required to mitigate affordable housing impacts according to this Chapter 23.58B if such development is located outside of a regional center or an urban center. 3. Developer's agreement. If the owner of the development required to mitigate affordable housing impacts according to this Chapter 23.58B is not the owner of the MHA-C units, then in addition to the agreement required according to subsection 23.58B.050.B.17, the owner of the development required to mitigate affordable housing impacts according to this Chapter 23.58B and the owner of the MHA-C units shall execute a developer's agreement, acceptable to the Director of Housing, allowing the exclusive use of the MHA-C units to satisfy the requirements of this Chapter 23.58B in return for necessary and adequate financial support to the development of the MHA-C units. 4. Letter of credit a. If the MHA-C units are located on a site other than the same lot as the development required to mitigate affordable housing impacts according to this Chapter 23.58B , the owner of the development required to mitigate affordable housing impacts according to this Chapter 23.58B shall provide to the Director of Housing an irrevocable bank letter of credit, approved by the Director of Housing, in the amount according to subsection 23.58B.040.A. b. The Director of Housing may draw on the letter of credit one year after the date of issuance of the certificate of occupancy, or, if a certificate of occupancy is not required, the final building permit inspection, for the development required to mitigate affordable housing impacts according to this Chapter 23.58B if the certificate of occupancy or final building permit inspection for the MHA-C units has not been issued on or before that date. The owner of the development required to mitigate affordable housing impacts according to this Chapter 23.58B shall also pay an amount equal to the interest on the cash contribution, at the rate equal to the prime rate quoted by Bank of America, or its successor, plus three percent per annum, from the date of issuance of the first building permit that includes the structural frame for the development required to mitigate affordable housing impacts according to this Chapter 23.58B . c. If and when the City becomes entitled to draw on any letter of credit, the Director of Housing may take appropriate steps to do so, and the amounts realized, net of any costs to the City, shall be used in the same manner as cash contributions according to subsection 23.58B.040.B. (Ord. 127375 , § 96, 2025; Ord. 126862 , § 14, 2023; Ord. 126855 , § 50, 2023; Ord. 126685 , § 47, 2022; Ord. 125835 , § 1, 2019; Ord. 125792 , § 9, 2019; Ord. 125791 , § 94, 2019; Ord. 125371 , § 17, 2017; Ord. 125363 , § 2, 2017; Ord. 125291 , § 38, 2017; Ord. 125267 , § 30, 2017; Ord. 125233 , § 10, 2016; Ord. 124895 , § 2, 2015)
Source: Seattle Municipal Code (Municode library)URL: https://library.municode.com/wa/seattle/codes/municipal_codeFetched: 7/25/2026