Total CFM Quantities for LEED

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Hi to all:

We have a baseline building using Type 3?PSZ systems for each thermal block as required by AHSRAE and LEED.? The proposed building uses? a combination of PVVT and PSZ systems as designed; one system?for?each thermal block, which is?the eQuest?suggested simulation method for PVVT systems.? The actual mechanical design conforms with 62.1-2004 and the drawings indicate a total building CFM of 14,000 +/- CFM.?

Its a?small building.

Here's the issue:
The baseline building CFMs are based on ASHRAE Appendix G requirements?and eQuest calculates the building total at 17,000 +/- CFM.? The simulated proposed building total = 19,000 +/- CFM using the same information on the drawings and then making CFM adjustments (adding some CFM; not thousands of CFM) to get the design within the 300 unmet hours and within 50 unmet hours of the baseline.

Baseline has no economizers and no ERVs.? Proposed design has integrated economizers, ERVs, and demand control ventilation for multi-occupant zones?with fluctuating occupant loads.? The engineer's?14,000+/- CFM design is based on Carrier's HAP program (we're using Carrier units).????

Questions:
1.? Any chance that LEED will review this and require that the actual design CFM of 14,000 +/- be revised to reflect the simulated 19,000 +/- CFM?? Or does anyone see something that's not quite right.

2.? We've actually got 10 units on this project,?should we?add 500 CFM to each unit (5K CFM to the building) to satisfy LEED's requirement that the documents reflect the HVAC modeled capacity?

Thanks for any help.

Ron Lamarre, AIA, NCARB
Architect - LEED AP

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