We received a comment back on a CI project stating:
"Demonstrate the system serving the special occupancy space is capable of modulating system and zone minimum supply volume below 0.30 cubic feet per minute per square foot of supply volume."
It then goes on to say:
"Confirm the mandatory requirements of ASHRAE 90.1-2007 and ASHRAE 62.1-2007 are met."
The ASHRAE 62.1-2007 calculation uses the minimum expected primary airflow. Now that there is a requirement to reduce the min airflow in this intermittently occupied space to 0.3 cfm/sf, the minimum expected airflow no longer meets the requirements of ASHRAE 62.1-2007. The purpose of ASHRAE 62.1 is to provide indoor air quality that is acceptable to human occupants. Here I seem to be getting penalized for not providing enough air to a space that is unoccupied.
I do not want to submit the 62.1 calc for IEQp1 at the minimum expected occupied design conditions to have the reviewer look at my schedule and see the VAV box min value (which has been set lower due to the intermittent unoccupied conditions) was not used, but I do not see a place in the IEQp1 form to note that this space has intermittent occupancy (the diversity variable is only applied at a system level, not per zone)
Roger Chang
Principal, Energy and Engineering LeaderDLR Group | Westlake Reed Leskosky
LEEDuser Expert
398 thumbs up
November 23, 2011 - 10:55 am
Rick, I've never seen a requirement specifically in ASHRAE 62.1 to modulate down to 0.3 cfm/sf. Is this a project specific requirement? Even an intermittently occupied space benefits from ventilation to combat off-gassing of materials within the space. I would provide a detailed response narrative, rather than trying to adjust the form to accommodate a specific condition.