The ASHRAE 62.1-2004 User\'s Guide includes an Excel calculation tool (ASHRAE Tool) which calculates system ventilation efficiency (Ev) and zone ventilation efficiency (Evz). Please advise whether use of the ASHRAE 62.1 User Manual Calculation Tool can be used to document compliance with this LEED credit. The ASHRAE Tool includes inputs for zone air distribution effectiveness (Ez) which is considered equivalent to air change effectiveness (ACE) as noted in EQc2 CIR ruling dated 07/20/2004. The ASHRAE Tool also includes inputs for Space Type, Floor Area of Zone, Design Population of Zone, and Design Discharge Airflow to Zone. The ASHRAE Tool seems to be an alternative method which can be used to determine compliance with this LEED credit. The ASHRAE Tool calculations also seems to be more current and accurate than the allowed LEED option as described in EQc2 CIR ruling dated 07/19/2004 which determines ADPI using an ASHRAE Handbook, and selects Ez from a table in Standard 62.1-2001, Addendum N. We propose the following calculation alternative which is based on the CIR ruling dated 07/19/2004 but has been adjusted if the ASHRAE Tool is used to document compliance with this LEED credit. LEED-NC v2.2 basis credit compliance on system ventilation efficiency (Ev). This method is similar but it identifies Evz values for each zone in both heating and cooling modes which are both required by the CIR ruling dated 07/19/2004. Zone__ADPI__Ez Heat__Ez Cool__Evz Heat__Evz Cool__Evz Min 1 2 n TABLE NOTES: (a) ADPI: Not required if using the ASHRAE 62.1-2004 User\'s Guide Excel Calculation Tool. (b) Ez Heat / Ez Cool: Based on ASHRAE 62-2004, Table 6.2, Zone Air Distribution Effectiveness. Ez Heat equals Ez in Heating Mode. Ez Cool equals Ez in Cooling Mode. (c) Evz Heat / Evz Cool: Based on results calculated by the ASHRAE 62.1-2004 User\'s Guide Excel Calculation Tool using Ez values. Evz Heat equals Evz in Heating Mode. Evz Cool equals Evz in Cooling Mode. (d) Evz Min: Minimum Evz value for heating and cooling modes. Must be greater than 0.90 to meet the requirements of this credit for each zone. We realize that the LEED-NC v2.2 rules can be used document this credit, but the restrictions imposed by the USGBC in using v2.2 rules to document this credit force it to also comply with v2.2 requirements for EQ Credit 1. The v2.2 rules are also based on increasing the minimum amount of fresh air by 30%, and not on achieving a minimum Evz 0.90.
CIR ruling dated 6/8/05 allows for the use of ASHRAE 62-2004 in lieu of ASHRAE 62-1999. If ASHRAE 62-2004 is applied, it must be applied consistently throughout a project in all associated prerequisites and credits referencing ASHRAE 62. Note that ADPI calculations are still required regardless of which version of ASHRAE Standard 62 is used, so Note (a) in the table above is incorrect. Applicable Internationally.