commentThe International Green Construction Code (IgCC) was finalized November 6, 2011, in Phoenix after a two-year development process. Although many jurisdictions have already adopted IgCC, the full code will not be published until March 2012.
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Courtesy International Code Council
The IgCC was finalized November 6 in Phoenix.
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Anyone familiar with the LEED rating systems or the ASHRAE standards will likely feel right at home with IgCC, which covers much of the same territory. In fact, ASHRAE 189.1 is referenced within the code as a possible compliance path, and cooperating sponsors of the code include the U.S. Green Building Council and ASHRAE itself (along with the American Institute of Architects, ASTM International, and the Illuminating Engineering Society).
However, code developers maintain that IgCC is not redundant but rather a necessary part of advancing sustainability in mainstream buildings: the code is intended to raise the “floor,” meaning the enforceable regulatory minimums, while giving voluntary certifications more flexibility to push the “ceiling” of high-performance possibilities ever higher. The code is also written to streamline with other international codes, including the International Building Code (IBC) already enforced throughout the U.S.
IgCC, when adopted by a jurisdiction, applies to all commercial buildings—both new and existing—as well as to all residential buildings over three stories. In addition to the many mandatory requirements, which represent the bulk of the code, jurisdictions may include their own requirements—such as light pollution control or stormwater management—and in some cases make exceptions to the code. Jurisdictions must also require individual projects to implement one to fourteen “electives.” Once chosen by the project owner, these electives—which include a range of items, from whole-building life-cycle assessment to site restoration to more stringent recycled-content options—become enforceable requirements for the building.
Some highlights from the fixed requirements:
- Site development and land use With some significant exceptions having to do with existing infrastructure, greenfield development is not permitted. When exceptions are made, there are clear guidelines for the extent of permitted site disturbance. Irrigation, erosion control, transportation, heat island mitigation, graywater systems, habitat protection, and site restoration are also addressed.
- Material resource conservation and efficiency At least 50 percent of construction waste must be diverted from landfills, and at least 55 percent of building materials must be salvaged, recycled-content, recyclable, biobased, or indigenous. Post-occupancy recycling options must also be available. A building service life plan is required, and the building must be designed to have a minimum 60-year service life.
- Energy conservation, efficiency, and atmospheric quality New buildings, renovations, and additions are required to have a zero energy performance index (zEPI) of 51, which code developers define as “51 percent of the energy allowable in the 2000 International Energy Conservation Code” (IECC); IgCC also requires building envelope performance to exceed IECC requirements by 10 percent. Certain levels of submetering and demand-response automation are required by the code, and minimum mechanical system requirements and distribution efficiency are addressed. The code provides guidance for renewable energy systems and includes extensive requirements for lighting system and plug load controls. Jurisdictions may optionally require post-occupancy energy performance reporting.
- Water conservation and efficiency IgCC establishes maximum flow rates for fixtures and water consumption limits for appliances depending on the building type. Hydronic heating systems may not use potable water. Extensive provisions for rainwater storage and graywater systems are included.
- Indoor environmental quality and comfort “Smoking shall not be allowed inside of buildings,” according to the code, which also addresses radon, asbestos, VOCs (referencing California regulations), sound transmission, and daylighting.
- Commissioning, operations, and maintenance Extensive pre- and post-occupancy commissioning is required by the code, along with the education of building owners and maintenance personnel.
IgCC includes a prescriptive path (a “cookbook” approach that smaller buildings may follow) and a modeled performance path (a more flexible approach to meeting energy performance targets, required for buildings over 25,000 square feet). During the final hearings, a third compliance path—an outcome-based approach advocated by a coalition comprised of the New Buildings Insititue (NBI), the U.S. Department of Energy, AIA, the Building Owners and Managers Association International, and the National Trust for Historic Preservation—was removed from the code. According to NBI communications director Stacey Hobart, the outcome-based code concept was well received, but committee members felt it was too new and were not quite ready to include it. The coalition plans to refine its proposal and resubmit it for the 2015 revision of IgCC.
Copyright 2011 by BuildingGreen Inc.
