2010 Green Factor Update
The City has expanded Green Factor to multifamily residential zones. New developments must achieve a minimum score of 0.50 in Midrise and Highrise zones, and 0.60 in Lowrise zones. For specific code language, please see approved ordinance 123495.
At the recommendation of the Urban Forestry Commission, the City also revised scoring to increase the credit awarded to trees and decreased the credit awarded to shrubs. Changes are reflected in the 2010 Score Sheet.
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.
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 project’s 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.
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 City’s growth management strategy as embodied in Seattle’s Comprehensive Plan. It responds to neighborhood plans for vibrant, pedestrian-oriented neighborhood centers.
January 3, 2011