2009 Green Factor Update Based on feedback from the public, developers, and design professionals, the City updated Green Factor standards in early 2009. Improvements include clearer organization and new credits such as shallow-profile green roofs, structural soil, and a bonus credit for food cultivation. Revisions are summarized in pages 7-8 of the âCommercial Code Clean-upâ Directorâs Report, and the actual code can be reviewed in Ordinance 122935. A new score sheet and worksheet are available, and a new Directorâs Rule provides additional interpretation. A recent study by The Berger Partnership provides a detailed and up-to-date description of the Green Factor and how it works. |
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The Green Factor is a landscape requirement designed to increase the quantity and quality of planted areas in Seattle while allowing flexibility for developers and designers to meet development standards. It currently applies to new development in commercial and neighborhood commercial zones outside of downtown, and is proposed for multifamily residential zones and the South Downtown planning area.
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Permit applicants in affected zones must demonstrate that their projects meet the Green Factor by using the Green Factor Score Sheet. The scoring system is designed to encourage larger plants, permeable paving, green roofs, vegetated walls, preservation of existing trees, and layering of vegetation along streets and other areas visible to the public. Bonuses are provided for food cultivation, native and drought-tolerant plants, and rainwater harvesting. As designers add landscape features, the score sheet automatically calculates a projectâs Green Factor score, allowing the applicant to easily experiment with different combinations.
Green Factor help maintain and improve livability in growing neighborhoods. In addition to being attractive, green elements in the landscape improve air quality, create habitat for birds and beneficial insects, and mitigate urban heat island effects. They also reduce stormwater runoff, protecting receiving waters and decreasing public infrastructure costs.
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The Green Factor was first adopted as part of the Neighborhood Business District Strategy (NBDS). NBDS, which revised commercial zoning requirements for the first time in many years, is intended to advance the Cityâs growth management strategy as embodied in Seattleâs Comprehensive Plan. It responds to neighborhood plans for vibrant, pedestrian-oriented neighborhood centers.






