23.44.080

A. Except as otherwise provided in this Section 23.44.080 , the maximum lot coverage allowed for structures is 50 percent. B. The following areas shall not be counted in calculating the lot size for the purpose of calculating lot coverage in this Section 23.44.080 : 1. Riparian corridors; 2. Wetlands and their buffers; 3. Submerged lands and areas within the shoreline setback; and 4. Designated non-disturbance area in steep slopes. C. Structures not counted. The following structures and portions of structures are not counted in lot coverage calculations: 1. Underground structures; 2. The first 36 inches of architectural features such as cornices, eaves, gutters, roofs, fireplaces, chimneys, and other similar features that project from principal and accessory structures; 3. Decks or parts of a deck that are 36 inches or less above existing grade; 4. Unenclosed porches or steps no higher than 4 feet above existing grade, or the grade at the street lot line closest to the porch, whichever is lower; and 5. Unenclosed structures that meet the standards of subsection 23.44.090.H. 6. Square footage of all Type A dwelling units, as defined in the Seattle Building Code, on any floor of a structure with up to ten stacked dwelling units. Any dwelling units above or below a Type A unit are not required to be Type A units to utilize this exception. D. The lot coverage allowed on lots containing areas listed in subsection 23.44.080.B shall not be less than 625 square feet or an amount of lot coverage approved by the Director through an environmentally critical area reduction, waiver, or modification pursuant to Chapter 25.09 , whichever is greater. E. For the purpose of this Section 23.44.080 , designated non-disturbance area in steep slopes shall include all portions of steep slope hazard areas except the following: 1. Areas that are granted relief from the prohibition of development according to Section 25.09.090 ; 2. Areas where development is allowed under a small project waiver according to Section 25.09.090 ; and 3. Areas where intrusion into the steep slope erosion hazard area and buffer is allowed by steep slope erosion hazard area variance according to Section 25.09.290 . F. Within a frequent transit service area, for development consisting entirely of dwelling units in structures that are less than three stories and that are arranged on up to three sides of a common ground-level amenity area equal to at least 20 percent of the lot area, that includes usable, contiguous community green space and trees, the maximum lot coverage allowed for structures is 60 percent. G. The maximum lot coverage allowed on lots with stacked dwelling units is 60 percent. (Ord. 127376 , § 31, 2025.)