AIA, NBI Partner on Energy Saving Code Revisions
Revision to IECC could reduce consumption up to 25 percent
How do you . . . offer well-vetted revisions for the International Energy Conservation Code to increase energy use reductions?
Summary: The AIA and New Buildings Institute (NBI) are submitting a set of comprehensive and integrated revisions for the International Energy Conservation Code (IECC) to achieve buildings that are 20-25 percent more energy efficient than what today’s average standards require and that are practical and feasible.
NBI is a national nonprofit group working to improve the energy performance of commercial buildings. It assesses new technologies, develops and promotes advanced design approaches, and provides support for policies that significantly improve the built environment. The AIA, in turn, is committed to the goal of reaching carbon neutrality for all buildings by 2030 and works with governmental bodies and professional and trade groups at the local, state, and federal levels to achieve that goal.
“In co-authoring this proposal, it was our intention to make sure that the new energy codes would be stringent enough to advance our stated goal of achieving carbon neutrality in buildings by 2030,” said AIA Executive Vice President/CEO Christine McEntee. “We feel it is important for the private sector to take a leadership position on this important issue that relates to the built environment."
The groups submitted their proposal to the International Code Council
June 1 for consideration in the current code development process.
The ICC develops energy codes that are part of overall model codes
for buildings triennially with the next update released in 2012.
The code proposal will be considered at the ICC hearings held at
the end of October in Baltimore.
The AIA/NBI proposal is based largely on NBI’s Core Performance Guide (CPG), which was originally published in October 2003 after thorough review and recommendations by a 23-person technical advisory committee. For this proposal, many elements of CPG have been revised, supplemented by other widely used sources, and recompiled to fit the format of the IECC, published by the International Code Council (ICC).
The criteria and specifications, in addition to publication in the CPG, have been implemented in multiple utility programs and in codes at the local and state levels. A version of CPG has been adopted by Massachusetts as a “stretch” code, and CPG is referenced in ordinances in Boulder, Colo., and the Adirondack region of New York State. Voluntary programs at Efficiency Vermont, National Grid, and We Energies, among many other utility programs, have used the CPG measure levels. These measures have been demonstrated to be pragmatic, widely vetted throughout the building and supply industries, and cost effective.
The bibliography of substantiating material, plus the technical information and technical substantiation, is available at NewBuildings.org.
This 2012 IECC proposal substantially revises Chapter 5 of the IECC with a series of measures and market-proven technologies that are integrated to achieve significant energy savings over current national model code. The proposal builds on and updates the 2009 IECC, plus it introduces some new elements such as commissioning of critical systems and a section on “additional efficiency package options” to offer flexibility in achieving these significant savings. Key elements of the proposal are:
- Building Envelope—Increases comfort and energy performance of the envelope through continuous air barriers, significant improvements in most glazing, reductions in thermal bridging, and increases in insulation levels. Comprehensive air barrier language is adapted from the Massachusetts building code, and envelope assemblies and u-values include specifications from CPG, 2009 IECC and proposed ASHRAE 90.1-2010.
- Mechanical Systems—Improves sections regarding economizers, incorporates more use of demand-controlled ventilation, includes efficiency improvements in mechanical equipment with some climate-specific flexibility, and provides additional calculation procedures for determining loads and equipment sizing. Design guidance is from CPG, economizer details are from ASHRAE 90.1-2007, and mechanical efficiency values are from CEE Tier 1 and ASHRAE 90.1-2007.
- Quality Assurance—Incorporates requirements for testing and commissioning of mechanical systems and performance testing of daylight related controls. Many CPG measures are written to ensure that building designs deliver actual energy performance, plus this proposal’s specific HVAC commissioning language is drawn from the Washington State energy code.
- Lighting—Reduces energy needed for lighting based on more efficient illuminating equipment and the use of several lighting control strategies. The LPDs are derived from CPG and ASHRAE/IESNA, and the control strategies are drawn from CPG.
- Daylighting—Includes additional availability of daylight sources combined with automatic daylight controls and comprehensive control strategy for all lighting zones. Daylight strategies are distilled from CA Title 24 and from CPG.
- Advanced Efficiency Package Options—A new Section 506 contains three approximately energy-equivalent packages to add to the savings. These additional package options are focused on HVAC equipment efficiency tables derived from the Consortium for Energy Efficiency (CEE) recommendations. (CEE is a North American collaborative effort of utilities, environmental groups, and industry.) Reduced Lighting Power Density tables are calculated using available high-efficacy illuminating products—proposed in Oregon and Washington—required automatic daylight controls in all daylit zones, and/or on-site renewable energy generation. These options round out the approximately final 3 percent in energy savings in the proposal, while also offering important flexibility in striving to approach 30 percent in overall energy savings.