Summary and critique of "LEED" 2009 Green Building Design & Construction Reference Guide
© 2010 Jonathan Ochshorn.
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Following is my summary and critique of the Green Building Design & Construction Reference Guide, 2009 Edition. Commentary on the Reference Guide can be found in these red boxes, sometimes within each of the chapter links immediately above, but mostly in my summary and critique of the prior version: Version 2.2 NC.
1. Introduction to LEED
Maximize both "economic and environmental performance."
Claims to be "transforming the built environment."
Responds to these problems:
- global climate change
- dependence on non-sustainable and expensive energy
- threats to human health
Consensus-based (18,000 member companies, organizations); committee based
Responds to these problems:
- buildings use more than 30% total energy; more than 60% electricity in US
- commercial buildings generate 1 billion metric tons CO2 in 2006, 30% more than in 1990
- toilets flush 5 billion gallons potable water per day
- commercial buildings produce 1.6 lbs solid waste per employee per day
- development replaces diverse habitats with hardscape
Claims of additional benefits:
- reduction of operating costs
- green buildings more marketable
- greater productivity
- less liability potential from IAQ issues
LEED has expanded beyond New Construction:
- LEED for Existing Buildings: Operations & Maintenance
- LEED for Core & Shell (i.e., speculative office construction)
- LEED for Schools
- LEED for Neighborhood Development
- LEED for Retail
- LEED for Healthcare
- LEED for Homes
- LEED for Commercial Interiors
Certification: 2008, created the Green Building Certification Institute (GBCI) to administer registration and certification of projects.
Principles of LEED:
Balance "established practice" with "emerging concepts."
Five categories are examined:
- Sustainable Sites (SS)
- Water Efficiency (WE)
- Energy and Atmosphere (EA)
- Materials and Resources (MR)
- Indoor Environmental Quality (IEQ)
Innovation in design (ID) is also examined (for green expertise and other issues not covered in the 5 categories).
Latest version 3 also has bonus points for addressing regional environmental issues or "priorities" (RP).
Credits and prerequisites:
- Each category contains "credits" for which points are given; in the latest version 3, these points are weighted to reflect their "potential environmental impact and human benefits" using TRACI software (EPA) and accounting for NIST weightings. The weights also reflect "the market implications of point allocation." The priorities of the latest guidelines are reduction of energy use and greenhouse gas emissions.
- Where prerequisites exist within a category, they must be met, although no points are given.
- Only positive integers are used for credits: no points are ever taken off for doing bad things (negative credits).
- 100 base points with another 10 ID or RP "bonus" points.
- Credits are assigned based on a comparison of the proposed building with a so-called "reference building" (i.e., a building designed without consideration of environmental or human damage, but legal under prevailing codes and standards).
- "Exemplary performance" credits are possible for being much more green than required by a credit; given through the "ID" category.
Of the 110 possible points, buildings need 40 to be certified. Other ratings are given as follows:
|80 or more points||platinum|
Buildings also need to meet Minimum Program Requirements (MPRs).
LEED for New Construction: intended for office buildings, but also used for most other commercial or institutional buildings, or for residential/hotel construction of 4 stories or more. Can be used for major renovations (i.e, with HVAC work, envelope work, and interiors work).
First posted 1 July 2010; last updated 1 July 2010