This past October, ASHRAE made several proposals to the International Code Council, which develops model codes that may be adopted by code jurisdictions in the United States or internationally. After a public review of the proposals, final hearings for the code change proposals take place May 21-22, 2007. If the proposals are accepted, they would be included in the 2007 code supplement.
“It is the governmental use of building codes and the conversion of standards into codes that derive the greatest benefit from the ASHRAE standards’ development process,” Terry Townsend, ASHRAE president, said at a meeting with ICC leadership, encouraging adoption of the proposals.
A proposal to include new ventilation rates from ANSI/ASHRAE Standard 62.1-2004, Ventilation for Acceptable Indoor Air Quality, was approved for inclusion in the International Mechanical Code (IMC). The change would lower zone ventilation in many zones, particularly those with high-occupant density, and improve overall ventilation results in systems where zones with differing ventilation requirements are served by a common ventilation system.
“For many high occupant-density zones (like classrooms and places of worship), these new rates reduce outdoor air intake requirements by 50% or more, compared to the IMC,” Dennis Stanke, chair of the Standard 62.1 committee, said. “HVAC systems for these buildings can be designed with fewer air conditioning tons and operated using less energy. Lower intake rates tend to reduce both first cost and operating cost.”
Four proposals written by ASHRAE’s Code Development Committee for ANSI/ASHRAE/IESNA Standard 90.1-2004, Energy Standard for Buildings Except Low-Rise Residential Buildings, and ANSI/ASHRAE Standard 90.2-2004, Energy-Efficient Design of Low-Rise Residential Buildings, were approved for inclusion in the International Energy Conservation Code.
• EC39: Lowers the solar heat gain coefficient requirements in residential buildings in Climate Zones 1 and 2 to 0.37 from 0.40. This requirement is consistent with Standard 90.2-2004.
• EC84: Adds a U-factor table to the code, and add definitions for C-Factors, and F-Factors.
• EC98: Adds a requirement for hot-gas-bypass to the code.
• EC125: Revises exterior lighting control requirements.
Also related to its energy standard, ASHRAE plans to submit a public comment on a proposal to provide R-Value, U-Factor requirements and removal of the Standard 90.1 envelope section as a compliance method. ASHRAE opposes approval of proposal EC82 because it removes a partial reference to Standard 90.1.
“While ASHRAE thinks the UA trade-off may be desirable, the envelope requirements and appendices of the standard should continue to be an alternative compliance pathway because they are technically based within a consensus process,” Townsend said.
Also approved was a proposal to make the IMC more consistent with ANSI/ASHRAE Standard 34-2004, Designation and Safety Classification of Refrigerants. The change would add new refrigerants for which the standard has given a designation and safety classification. The addition will facilitate use of these refrigerants.