Downtown Office Core 1, Downtown Office Core 2, and Downtown Mixed Commercial upper-level development standards
Seattle Mun. Code § 23.49.058
in effectA. For purposes of this Section 23.49.058 , except in zones with a mapped height limit of 170 feet or less, a "tower" is a portion of a structure, excluding rooftop features permitted above the applicable height limit pursuant to Section 23.49.008 , in which portion all gross floor area in each story is horizontally contiguous, and which portion is above (i) a height of 85 feet in (a) a structure that has any non-residential use above a height of 65 feet or does not have residential use above a height of 160 feet or contains an elementary or secondary school; or (ii) in any structure not described in clause (i) a height determined as follows: 1. For a structure on a lot that includes an entire block front or that is on a block front with no other structures, 65 feet; 2. For a structure on a lot abutting 3rd Avenue between Union Street and Pike Street that contains only residential uses above a height of 65 feet, 85 feet; or 3. For a structure on any other lot, the height of the facade closest to the street property line of the existing structure on the same block front nearest to that lot, but if the nearest existing structures are equidistant from that lot, then the height of the higher such facade; but in no instance shall the height exceed 85 feet or be required to be less than 65 feet. B. Facade modulation and upper-level width limit 1. The requirements of subsections 23.49.058.B.2 and 23.49.058.B.3 apply to: a. All structures 160 feet in height or less, and all structures in the DMC 170 zone, in which any story above an elevation of 85 feet above the adjacent sidewalk exceeds 15,000 square feet. For structures with separate towers, the 15,000 square foot threshold applies to each tower individually; and b. Portions of structures in non-residential use above a height of 160 feet, excluding structures in the DMC 170 zone, in which any story above an elevation of 85 feet exceeds 15,000 square feet. For structures with separate towers, the 15,000 square foot threshold applies to each tower individually. 2. The following facade modulation requirements apply to structures meeting subsection 23.49.058.B.1: a. In DOC1, DOC2, and DMC zones, except the DMC 170 zone, facade modulation is required above a height of 85 feet above the sidewalk for any portion of a structure located within 15 feet of a street lot line. No modulation is required for portions of a facade set back 15 feet or more from a street lot line. b. In the DMC 170 zone, facade modulation is required above a height of 60 feet above the sidewalk for any portion of a structure located within 15 feet of a street lot line. No modulation is required for portions of a facade set back 15 feet or more from a street lot line. c. The maximum length of a facade without modulation is prescribed in Table A for 23.49.058. This maximum length shall be measured parallel to each street lot line, and shall apply to any portion of a facade, including projections such as balconies, that is located within 15 feet of street lot lines. Table A for 23.49.058 Modulation requirements for DOC1, DOC2, and DMC zones, except DMC 170 zone Elevation (in feet) Maximum length of unmodulated facade within 15 feet of street lot line (in feet) 0 to 85 No limit Greater than 85, up to 160 155 Greater than 160, up to 240 125 Greater than 240, up to 500 100 Above 500 80 Modulation requirements for DMC 170 zone 0 to 60 No limit Above 60 125 d. Any portion of a facade exceeding the maximum length of facade prescribed on Table A for 23.49.058 shall be set back a minimum of 15 feet from the street lot line for a minimum distance of 60 feet before any other portion may be within 15 feet of the street lot line. 3. The following upper-level width limit requirements apply to structures meeting subsection 23.49.058.B.1: a. On lots where the width and depth of the lot each exceed 200 feet, the maximum facade width for any portion of a structure above 280 feet shall be 145 feet along the general north/south axis of a site (parallel to the Avenues), and this portion of the structure shall be separated horizontally from any other portion of a structure on the lot above 280 feet by at least 80 feet at all points. b. In the DMC 170 zone, the maximum facade width of any portion of a structure above 60 feet in height shall be 180 feet along lots fronting on Alaskan Way or Western Avenue between University and Union Streets. This portion of the structure shall be separated horizontally from any other portion of a structure on the lot above 60 feet in height by at least 30 feet at all points. If the separation between portions of a structure above 60 feet in height is less than 30 feet, the widths of the separated portions of the structure shall be combined to determine the structure's width. C. Tower floor area limits and tower width limits for portions of structures in residential use. The requirements of this subsection 23.49.058.C apply only to structures that include portions in residential use above a height of 160 feet, and do not apply in the DMC 170 zone. 1. Maximum limits on average residential gross floor area per story and maximum residential floor area per story of towers are prescribed in Table B for 23.49.058. Table B for 23.49.058 Average residential gross floor area per story and maximum residential gross floor area per story of a tower 1 (1) Zone (2) Average residential gross floor area limit per story of a tower if height does not exceed the base height limit for residential use (3) Average residential gross floor area limit per story of a tower if height exceeds the base height limit for residential use (4) Maximum residential floor area of any story in a tower DMC 240/290-440 and DMC 340/290-440 10,000 square feet 10,700 square feet 11,500 square feet DOC2 15,000 square feet 12,700 square feet 16,500 square feet DOC1 15,000 square feet 14,800 square feet 16,500 square feet Footnote to Table B for 23.49.058 1 For the height at which a "tower" begins, see the definition in subsection 23.49.058.A. a. For structures that do not exceed the base height limit for residential use, each tower is subject to the average floor area per story limits specified in column (2) on Table B for 23.49.058. b. For structures that exceed the base height limit for residential use according to Chapter 23.58A , the average residential gross floor area per story of each tower is subject to the applicable maximum limit specified in column (3) on Table B for 23.49.058. c. In no instance shall the residential gross floor area of any story in a tower exceed the applicable maximum limit specified in column (4) on Table B for 23.49.058. d. Unoccupied space provided for architectural interest pursuant to subsection 23.49.008.B shall not be included in the calculation of gross floor area. 2. Maximum tower width a. In DMC zones, the maximum facade width for portions of a building above 85 feet along the general north/south axis of a site (parallel to the Avenues) shall be 120 feet or 80 percent of the width of the lot measured on the Avenue, whichever is less, except that: 1) On a lot where the limiting factor is the 80 percent width limit, the maximum facade width is 120 feet, if at all elevations above a height of 85 feet, no more than 50 percent of the area of the lot located within 15 feet of the street lot line(s) is occupied by the structure; and 2) On lots smaller than 10,700 square feet that are bounded on all sides by street right-of-way, the maximum facade width shall be 120 feet. b. In DOC2 zones, the maximum facade width for portions of a building above 85 feet along the general north/south axis of a site (parallel to the Avenues) shall be 145 feet. c. In DOC1, the maximum facade width for portions of a building above 85 feet along the general north/south axis of a site (parallel to the Avenues) shall be 160 feet. d. The projection of unenclosed decks and balconies, and architectural features such as cornices, shall be disregarded in calculating the maximum width of a facade. D. Tower spacing in DMC zones 1. The requirements of this subsection 23.49.058.D apply to all structures over 160 feet in height in DMC zones, excluding DMC 170 zones, except that no separation is required: a. Between structures on different blocks, except as may be required by view corridor or designated green street setbacks; or b. From a structure on the same block that is not located in a DMC zone; or c. From a structure allowed pursuant to the Land Use Code in effect prior to May 12, 2006; or d. From a structure on the same block that is 160 feet in height or less, excluding rooftop features permitted above the applicable height limit for the zone pursuant to Section 23.49.008 ; or e. From a structure in a DMC 170. 2. Except as otherwise provided in this subsection 23.49.058.D, in the DMC 240/290-440 zone located between Stewart Street, Union Street, Third Avenue, and First Avenue, if any part of a tower exceeds 160 feet in height, then all portions of the tower that are above 125 feet in height shall be separated from any other existing tower that is above 160 feet in height, and the minimum separation required between towers from all points above the height of 125 feet in each tower is 60 feet. 3. Except as otherwise provided in this subsection 23.49.058.D, in a DMC zone with a mapped height limit of more than 170 feet located either in Belltown, as shown on Map A for 23.49.058, or south of Union Street, if any part of a tower exceeds 160 feet in height, then all portions of the tower that are above 125 feet in height must be separated from any other existing tower that is above 160 feet in height, and the minimum separation required between towers from all points above the height of 125 feet in each tower is 80 feet. Map A for 23.49.058 Belltown 4. Except as otherwise provided in this subsection 23.49.058.D, in a DMC zone with a mapped height limit of more than 170 feet located in the Denny Triangle, as shown on Map A for 23.49.056, if any part of a tower exceeds 160 feet in height, then all portions of the tower that are above 125 feet in height must be separated from any other existing tower that is above 160 feet in height, and the minimum separation required between towers from all points above the height of 125 feet in each tower is 60 feet. 5. The projection of unenclosed decks and balconies, and architectural features such as cornices, shall be disregarded in calculating tower separation. 6. If the presence of an existing tower would preclude the addition of another tower proposed on the same block, as a special exception, the Director may waive or modify the tower spacing requirements of this Section 23.49.058 to allow a maximum of two towers to be located on the same block that are not separated by at least the minimum spacing required in subsections 23.49.058.D.2, 23.49.058.D.3, and 23.49.058.D.4, other than towers described in subsection 23.49.058.D.1. The Director shall determine that issues raised in the design review process related to the presence of the additional tower have been adequately addressed before granting any exceptions to tower spacing standards. The Director shall consider the following factors in determining whether such an exception shall be granted: a. Potential impact of the additional tower on adjacent residential structures, located within the same block and on adjacent blocks, in terms of views, privacy, and shadows; b. Aspects of the proposal that offset the impact of the reduction in required separation between towers, including the provision of public open space, designated green street or other streetscape improvements, and preservation of Landmark structures; c. Potential impact on the public environment, including shadow and view impacts on nearby streets and public open spaces; d. Design characteristics of the additional tower in terms of overall bulk and massing, facade treatments and transparency, visual interest, and other features that may offset impacts related to the reduction in required separation between towers; e. The City's goal of encouraging residential development downtown; and f. The feasibility of developing the site without an exception from the tower spacing requirement. 7. For purposes of this Section 23.49.058 a tower is considered to be "existing" and must be taken into consideration when other towers are proposed, under any of the following circumstances: a. The tower is physically present, except that a tower that is physically present is not considered "existing" if the owner of the lot where the tower is located has applied to the Director for a permit to demolish the tower and provided that the no building permit for the proposed tower is issued until the demolition of the tower that is physically present has been completed; b. The tower is a proposed tower for which a complete application for a Master Use Permit or building permit has been submitted, provided that: 1) The application has not been withdrawn or cancelled without the tower having been constructed; and 2) If a decision on that application has been published or a permit on the application has been issued, the decision or permit has not expired, and has not been withdrawn, cancelled, or invalidated, without the tower having been constructed. c. The tower is a proposed tower for which a complete application for early design guidance has been filed and a complete application for a Master Use Permit or building permit has not been submitted, provided that the early design guidance application will not qualify a proposed tower as an existing tower if a complete Master Use Permit application is not submitted within 90 days of the date of the early design guidance public meeting if one is required, or within 90 days of the date the Director provides guidance if no early design meeting is required, or within 150 days of the first early design guidance public meeting if more than one early design guidance public meeting is held. Failure to file a complete Master Use Permit application within 12 months of filing a complete application for early design guidance or from November 4, 2024 shall disqualify a proposed tower from being considered an existing tower. E. Upper-level setbacks 1. If a lot in a DMC zone is across a street from the Pike Place Market Historical District, as shown on Map 1K, a continuous upper-level setback of 15 feet, measured from the street lot line across the street from the Pike Place Market Historical District, is required for all portions of a structure above a height of 65 feet. 2. If a lot in a DMC or DOC2 zone is located on a designated green street that is not a designated view corridor requiring view corridor setbacks according to Section 23.49.024 , as shown on Map 1D, View Corridors, a continuous upper-level setback of 15 feet, measured from the abutting green street lot line, is required for portions of the structure above a height of 45 feet. F. Structure separation requirements for mid-block corridors in a DMC zone in South Downtown. On a lot in a DMC zone in South Downtown, as depicted on Map 1A, the following standards apply: 1. At all levels above 45 feet and up to 85 feet in height, structures separated by a mid-block corridor must be separated at all points by a minimum horizontal distance of 45 feet, unless subsection 23.49.058.F.3 applies. 2. At all levels above 85 feet in height, structures separated by a mid-block corridor must be separated at all points by a minimum horizontal distance of 55 feet, unless subsection 23.49.058.F.3 applies. 3. If a mid-block corridor abuts a side lot line that is not a street lot line, at all levels above 45 feet, structures on that lot must set back from that side lot line at all points by a minimum horizontal distance of 45 feet. (Ord. 127099 , § 33, 2024; Ord. 126917 , § 2, 2023; Ord. 126855 , § 35, 2023; Ord. 125291 , § 23, 2017; Ord. 125272 , § 42, 2017; Ord. 125173 , § 7, 2016; Ord. 124680 , § 10, 2015; Ord. 123589, § 23, 2011; Ord. 123046, § 65, 2009; Ord. 122235, § 9, 2006; Ord. 122054, § 46, 2006; Ord. 120967, § 7, 2003; Ord. 120443 , § 28, 2001; Ord. 119728, § 5, 1999; Ord. 112519, § 10, 1985; Ord. 112303, § 3(part), 1985.)
Source: Seattle Municipal Code (Municode library)URL: https://library.municode.com/wa/seattle/codes/municipal_codeFetched: 7/25/2026