Green Roofs - Living Architecture Monitor - Spring 2011 - (Page 32)

INNOVATION WHAT THE INTERNATIONAL GREEN CONSTRUCTION CODE (IGCC) SAYS ABOUT GREEN ROOFS IGCC PV2 uses the term vegetative roof (per Chapter 2, deﬁnitions): Vegetative Roof: An assembly of interacting components designed to waterproof and normally insulate a building’s top surface that includes, by design, vegetation and related landscaping elements. Extensive Vegetative Roof: A low-proﬁle roof with a growing medium less than eight inches in depth, composed of plants that can thrive in a rooftop environment with limited water, shallow roots and sparse nutrients. Intensive Vegetative Roof: A high-proﬁle roof with a growing medium eight inches or more in depth that can support a wide range of vegetables, shrubs and small trees. Code requirements pertaining to vegetative (green) roofs are mostly in Chapter 4 and cover such areas as: turf grass (“Not more than 40 percent of the area of the vegetated area of the building site shall be planted with turf grass”); roof coverings; roof solar reﬂectance and thermal emittance; roof products testing (“Roof products shall be tested for a minimum three-year aged solar reﬂectance in accordance with ASTM E1918, ASTM C1549 or Test Method One of CRRC-1 Standard and thermal emittance in accordance with ASTM C1371 or ASTM E408, and shall comply with the minimum values in Table 404.3.1.”); solar reﬂectance index; and engineered growing media. Additionally, there are some requirements for operations and maintenance plans in Chapter 9. Source: Dru Meadows, AIA, CCS, FCSI, the GreenTeam, Inc. in Tulsa, Oklahoma. because the code does not yet clearly define the enforcement authority (and penalties for non-compliance) available to code officials. At the same time, the strength of any code – green building codes included – is its ability to redefine what the minimum acceptable levels of risk will be. The enforcement infrastructure already in place underscores the obligation of the green building movement to unleash the potential of tens of thousands of code officials implementing these next-generation preventive measures and to continue pressing forward. FULL-STEAM AHEAD The ongoing process of updates to all of these documents is requiring building industry professionals to be on our toes and to actively engage. LEED’s next version is currently under development and reopened for public review in June. The month of May offered the opportunity for public input on the IGCC at in-person code development hearings, with a final round of written comments to be accepted in August and heard publicly in November. ASHRAE’s Standing Standard Project Committee processes comments and publishes updates to Standard 189.1, with its next full version expected before end of year. Amidst all the developments between each of these codes and standards, one thing is certain: there’s no turning back. In fact, as an attempt to meet current demand from the so many state and local jurisdictions engaged in sustainability planning, the International Code Council released the first two “public versions” of the IGCC long before the full review and approval by the Code Council’s membership of building officials. Code-hungry jurisdictions should be pleased to know that the IGCC’s inclusion of the fully published Standard 189.1 as an alternate path to compliance adds further present-day legitimacy to the code. Adopting it this way would essentially provide an IGCC book sleeve around the Standard 189.1 content, leaving the door open for both fully published documents come spring of 2012. In the end, tomorrow’s best outcomes will be driven by a combination of rating systems and codes. Truly sustainable buildings and communities are achievable if we leverage the distinct and complementary strengths of these tools. The remaining effort to educate and mobilize everyone involved is no small task. So rest while you can – for we have much work yet to do. Jeremy Sigmon, LEED AP, is building codes advocacy manager at the U.S. Green Building Council in Washington, D.C. He holds a Bachelor of Arts from Washington University in St. Louis, Missouri, has been intimately involved in steering the development of green building codes and standards alongside USGBC’s LEED green building rating system. LEARN MORE & GET INVOLVED Greening the Codes – a USGBC white paper available at: www.usgbc.org International Green Construction Code – www.iccsafe.org Standard 189.1 – www.ashrae.org/greenstandard California Green Building Standards Code - www.usgbc.org USGBC Policy Brief on LEED and Green Building Codes – www.usgbc.org http://www.usgbc.org/ShowFile.aspx?DocumentID=7403 http://www.iccsafe.org/igcc http://www.ashrae.org/greenstandard http://www.usgbc.org/News/PressReleaseDetails.aspx?ID=4367 http://www.usgbc.org/DisplayPage.aspx?CMSPageID=2501

Table of Contents for the Digital Edition of Green Roofs - Living Architecture Monitor - Spring 2011

Green Roofs - Living Architecture Monitor - Spring 2011
Contents
Adaptation Through Innovation
Award-Winning Leader
Living Building Challenge Update
On the Roof With...
The Black Arts
Green Walls
Stormwater Policy
Root Repellent Standards
Growing Media
Green Building Codes
New Corporate Members
The GRP Turns Two
Professional Calendar
My First Year as a GRP

Green Roofs - Living Architecture Monitor - Spring 2011