ATLANTA — With the 2013 version of the ASHRAE/IES energy standard scheduled for publication later this year, ASHRAE said a number of changes are being proposed to strengthen its requirements. A total of 26 proposed addenda to ANSI/ASHRAE/IES Standard 90.1-2010, Energy Standard for Buildings Except Low-Rise Residential Buildings, are currently open for public comment.

“As we move toward publication of the 2013 standard, the 90.1 committee is considering many changes to reduce building energy use and cost,” said Steve Skalko, chair. “The proposed addenda reflect a variety of changes to the standard, many of which are the result of earlier public review comments. These changes contribute to our goal of making the standard 40 to 50 percent more stringent than the 2004 standard.”

The energy cost goals for the 2013 standard are:

• Regulated loads only – 50 percent target, which includes only regulated energy end use loads as included in the Standard 90.1-2004 baseline.

• Whole building – 40 percent target, which includes all energy end uses.

Twenty-two proposed addenda are open for public comment until April 21, 2013:

• aa mandates direct digital control (DDC) for certain applications in both new buildings and retrofits where cost effective and defines the minimum capability of mandated DDC systems.

• bo adds requirements for use of gas condensing service water heaters in newly constructed buildings.

• bs reduces the occupancy threshold for demand controlled ventilation from greater than 40 people per 1,000 square feet, with exemptions for certain occupancies, to equal to or greater than 25 people per 1,000 square feet, expanding the occupancies where demand controlled ventilation is required.

• co corrects the calculation of hotel and motel type guestroom spaces based on an error in applying the room geometry of the space type, which then changes the associated whole building lighting power densities (LPDs) for hotel and motel.

• cr modifies the designation for the types of facilities eligible for the higher LPDs based on use of space for those needing additional lighting for age and other related eye issues.

• ct corrects an error for the addition of HVAC systems to heated only storage areas in Appendix G. The single zone systems would be assigned to a single thermal zone vs. being grouped with the multiple zone systems.

• cw uses the new SS-EN ISO 25745-1:2012 to add a movement energy efficiency requirement for elevators.

• cy revises the requirements for the use of exhaust air energy recovery as defined in 6.5.6.1. In 2012, addendum bt expanded down the range for the use of exhaust air energy recovery to 10 percent ventilation rates. In addition, energy recovery was removed for climate zones 3B, 3C, 4B, 4C, and 5B for >70 percent outside air. These changes were based on the latest performance and economics analysis.

• cz ensures revisions to a table and new footnotes are consistent with Section 303 of the Energy Independence and Security Act of 2007 (EISA 2007), which increased the federal minimum efficiency standards for residential-sized boilers. Section 303 increased the minimum annual fuel utilization efficiency for gas and oil-fired boilers, and established design requirements for certain types of new boilers manufactured or imported for use in the United States. All of the efficiency and design requirements took effect for equipment built on or after Sept. 1, 2012.

• da provides two compliance paths for high speed doors within the Mandatory Air Leakage requirements. It also clarifies which test glazed overhead doors are to follow.

• db addresses an error in addendum bb contained within Table 5.5-3, under the category “Floors, Steel Joist” and in the cells assigned to the “residential” occupancy.

• dc clarifies that rooms within suites should be handled individually when one becomes empty.

• dd clarifies the exception to re-roofing and roof re-covering.

• de revises the design point for waterside economizers in computer room applications.

• df replaces current minimum performance requirements for packaged Computer Room Air Conditioners shown in Table 6.8.1k with a new table based on Standard 127-2012. The standard had referenced the 2007 version of Standard 127, Method of Testing for Rating Computer and Data Processing Room Unitary Air Conditioners. AHRI and member companies have agreed to test their equipment under the new standard. The test configurations were increased and the performance values updated accordingly.

• dg changes the reference to the 2012 ANSI/CRRC Standard from the 2010 version.

• di prohibits use of fossil fuels and electricity for humidification above 30 percent rh and dehumidification to 60 percent rh, except in special circumstances. Where control is required within the 30-60 percent region, a deadband is required. Where even tighter control is mandated, the system is exempted.

• dj offers an increase in electrical/mechanical rooms in cases where the current proposed allowance of 0.42 W/sq ft is not considered sufficient to provide needed vertical and horizontal illuminance given the varied configuration of electrical/mechanical rooms. The additional allowance would have to have separate control and could not be traded off to other spaces in the building.

• dk eliminates the exemption for wattage used in spaces where lighting is specifically designed for those with age related or other medical condition related eye issues where special lighting or light levels might be needed.

• dl corrects the calculation of hotel and motel type guestroom spaces based on an error in applying the room geometry of the space type and combines them into a single value since the calculated value is determined to be the same for code purposes.

• dn revises the requirements for the use of hot gas bypass as defined in section 6.5.9 and table 6.5.9.

• do is updating referenced standards in various provisions covering mechanical systems in 90.1-2010.

One addendum is open for public review until April 28, 2013:

• Addendum cv develops baseline energy use guidance for public assembly spaces toward assessing energy performance achievement of a proposed building. Public assembly spaces are typically designed and operated differently than surrounding spaces.

In addition, three addenda under review that received public comments in earlier reviews have been revised and are open for public comment until May 6, 2013:

• ac provides for two compliance paths with regard to utilizing air spaces in conjunction with reflective surfaces.

• bm makes the baseline building in Appendix G equivalent to 90.1-2004 for interior lighting design.

• cl modifies IEER requirements for the air cooled air conditioners ≥65,000 Btuh and < 135,000 Btuh to increase the IEER from 12.8 to 12.9 for electric resistance heating units and 12.6 to 12.7 for gas fired units. It also revises air cooled heat pumps ≥65,000 Btuh and < 135,000 Btuh for electric resistance heating units from 12.0 to 12.2 and from 11.8 to 12.0 for gas fired units.

For more information, visit www.ashrae.org/publicreviews.

Publication date: 4/8/2013