ASHRAE Proposes Changes to Green Standard

ASHRAE is proposing five additions to its green building design standard.

The proposals mainly focus on reducing the heat island effect through landscaping, cool roof standards, paving materials, and pedestrian accommodations. If adopted, the changes would modify Standard 189.1-2009, Standard for the Design of High-Performance Green Buildings Except Low-Rise Residential Buildings to:

• Extend the 5-year tree growth rate to 10 years, allowing more species diversity and restrict the use of invasive plants
• Include aged values for the solar reflective index and a reference to the Cool Roof Rating Council ANSI Standard
• Treat porous pavers and open-graded aggregate, which mitigate the heat island effect, separately from other paving materials
• Exempt dry climates from HVAC condensate collection requirements
• Require designated walkways to ensure pedestrian-friendly environments