Phoenix Downtown Area General Standards and Guidelines

Downtown area requirements include shade standards, with a percentage of shade coming from trees; landscape standards, such as a 30 percent tree canopy coverage and 50 percent living vegetation ground coverage per site; tree species guidelines; the use of permeable paving materials for hardscaping, areas adjacent to tree wells, and walkways; the planting of trees and bioswales in landscaping strips on streets without on-street parking, tree planting requirements for streets with on-street parking; the prohibition on building downspouts draining onto sidewalks, proposed building orientation to minimize heat gain and consider the impact of shade on adjacent areas; green roofs to meet open space requirements, as well as Solar Reflective Index (SRI) requirements; and window guidelines to reduce summer solar heat gain and reflectivity.

Green roofs may be counted toward open space (useable or passive) requirements. Occupiable green roofs should comply with open space landscaping and shade standards and be accessible to all building occupants.
(1) Roof should have the following Solar Reflective Index (SRI) for 75% of the roof surface:
(A) 78 SRI for low-sloped that have a slope less than 2:12.
(B) 29 SRI for steeped sloped roofs that have slopes greater than 2:12.
(C) A green roof that covers 75% of the roof area may be used in lieu of an SRI roof.