Clarification Response Narrative— Indoor Environmental Quality Project ID: 1000026559 Rating system & version: LEED-NC v2009 Project registration date: 08/09/2012

IEQp1: Minimum Indoor Air Quality Performance Issue #1: It appears that the calculations may not have been performed for the worst-case conditions. Generally, worst-case conditions are during heating mode (zone air distribution effectiveness, Ez, of 0.8 for an overhead distribution system in heating mode.) and when the VAV system is at minimum flow. For example, in the 62MZCalc for AHU-1 in the heating mode, the CV-1-2/CV-1-3 uses a design total supply to zone of 2,760 which is greater than the fan powered VAV terminal units schedule on M603 which shows that the maximum cfm was designed to be 2,624 cfm. Additionally, the percent of total design airflow rate at condition analyzed is 100%. This is unexpected for a VAV box at the worst-case conditions. Further, only the first zone uses a zone air distribution effectiveness Ev=0.80. All of the remaining zones use 1.0. Technical Advice #1: Provide revised Ventilation Rate Procedure calculations with an Ez of 0.8 and with the VAV boxes analyzed at minimum flow, or provide additional information to justify the parameters utilized. Response #1: JJA replaced the previously submitted 62MZCalc spreadsheets with ASHRAE Standard 62.1 calculation performed by TRACE 700. The uploaded reports demonstrate compliance with the provided technical advice. After the calculation, schedules were re-issued and uploaded to match updated calculations.

IEQp1: Minimum Indoor Air Quality Performance (continued) Issue #2: It appears that all occupiable space (as defined by ASHRAE 62.1-2007) has not been accounted for within the ventilation rate procedure calculations. For instance, the calculator for AHU-2 includes only three zones totaling 3,110 square feet while M601 lists the area served by this unit as 26,900 square feet. Note that all occupiable spaces (which can include regularly occupied, non-regularly occupied, and unconditioned areas) must be provided with ventilation which meets the minimum requirements in accordance with ASHRAE 62.1-2007. Similar discrepancies occur for many of the units. Technical Advice #2: Update the Ventilation Rate Procedure calculations to include all occupiable space. Note that for air handling units serving more than ten ventilation zones, it is acceptable to provide a calculation which combines some of the zones for the purposes of ventilation calculations. The first ten zones listed for the project must be individual ventilation zones, and must be the most likely candidates for the critical zone (e.g. spaces with high occupant density such as conference rooms and meeting spaces, and spaces with low minimum flow per unit area or per person). It is acceptable to include less than ten potentially critical zones within the calculator if a narrative is provided that adequately describes the evaluation process that was used to narrow the number of zones. The remaining ventilation zones listed may group a large number of spaces, as long as the space occupant category is the same (e.g. office), the space population density is similar, the value for zone air distribution effectiveness, Ez, is the same, and the Vpz value per unit floor area is similar. The values for Az, Vbz, Voz, and Vdzd should be entered as the sum of the values for all ventilation zones that are grouped into a single zone, and the value for Ds should be based on the weighted average minimum flow rate for all of the ventilation zones grouped into a single zone. The supplemental narrative should clearly denote which ventilation zones are grouped. If the minimum required ventilation rate exceeds the as designed ventilation rate, provide revised mechanical schedules or a test and balance report verifying the minimum required ventilation rate is met. Response #2: All occupied spaces were included the submitted ASHRAE Standard 62.1 calculation performed by TRACE 700. Unoccupied spaces, spaces that are occupied less than 5% are excluded from the calculations; mechanical and electrical rooms, stairs, etc. The outside air was calculated using TRACE 700. The Z-value was adjusted to make the calculated critical zones more closely align with the higher density rooms. The purpose of the Z-value is to make sure that the calculation doesn’t base its critical room outside airflow on a remote storage closet or empty corridor. The rooms that were identified as critical are noted with an asterisks in the provided PDF report.

IEQp1: Minimum Indoor Air Quality Performance (continued) Issue #3: It is unclear how the percentage of design airflow at the condition analyzed (Ds) was determined for the project. The system level value is reported as 58%, and the values reported for the ventilation zones are all 100%, which is unexpected for a Variable Volume system. Technical Advice #3: Provide additional information regarding the selection of Ds, revise the calculation as necessary to be consistent with the flow conditions for the worst-case conditions analyzed (most likely heating mode), and confirm that the value for Ds is correct both at the zone level and at the system level. Note that if the weighted average value for Ds at the zone level is 0.3, the system level value would also be anticipated to be 0.3. Response #3: This error is corrected by the system selection on TRACE 700. Issue #4: The VRP calculations for AHU(s)-11, 12, and 13 were performed using the 62MZCalc spreadsheet following ASHRAE 62.1-2004 Section 6.2.5, which is appropriate for multiple zone reticulating systems. However, these systems serve a single ventilation zone; therefore, the multiplezone recirculation calculation methodology is inappropriate. Section 6.2.3 should be followed when calculating the minimum outside air rate for single zone systems. Additionally, it appears that the calculations for the single zone FCUs and AHU-14 were omitted. Technical Advice #4: Revise the VRP calculations for AHU(s)-11, 12, and 13 and provide the VRP calculations for AHU-14 and the FCUs to follow Section 6.2.3. If the minimum required ventilation rate exceeds the as designed ventilation rate, provide revised mechanical schedules or a test and balance report verifying the minimum required ventilation rate is met. Please note that the ASHRAE 62MZ calculator should not be used for single zone systems showing compliance with Section 6.2.3; the Prerequisite Form should be utilized for these systems. Response #4: The FCU’s and AHU-14 serve unoccupied areas such as mechanical rooms and data/electrical room; therefore, they were omitted from ASHRAE Standard 62.1 2007 calculation performed by TRACE 700. AHU-13 does have a few series fan power boxes associated with it; therefore, it has multiple zones. It was incorrect to calculate AHU 11 & 12 as multiple zones. System type selection within TRACE has resolved this mistake.

IEQp1: Minimum Indoor Air Quality Performance (continued) Issue #5: It appears that the calculations for the 100% outdoor air units AHUs 16 and 17 were omitted. Technical Advice #5: Provide the VRP calculations for the 100% outdoor air units AHUs 16 and 17. Note that v5.0 of the form has a calculator for 100% outdoor air systems embedded in it which should be used for these systems. Response #5: AHUs 15, 16, &17 are 100% dedicated outside air systems that do not directly deliver filtered and conditioned outside air directly to an occupied space but the other air-handling units that provide conditioned supply air to the occupied space. The TRACE 700 program does not have a way to model a 100% dedicated outside air-handling unit to multiple air-distribution systems. The outside air riser diagrams on Sheet M4.03 shows how AHU-16 and AHU-17 delivers metered outside air to the AHU Rooms through VAV Terminal units. The VAV Terminal Schedule on M6.03 has the minimum outside air quantities scheduled for each air-handling unit as determined by ASHRAE Standard 62.1 calculation performed by TRACE 700.