855773667-LEED-v5-O-M-Reference-Guide-Launch-Edition-1 - Page 244
Extracted Content
- Multiple-zone recirculating system . Multiply the uncorrected outdoor air flow for the system (Vou) by 1.15 (or 1.30 if pursuing 30% threshold). Multiply the breathing zone outdoor airflow for the critical zone (Vbz for critical zone) by 1.15 (or 1.30 if pursuing 30% threshold). Calculate the new system ventilation efficiency (Ev) using the updated values for Vou and the critical zone Vbz, and recalculate the required outdoor air intake flow for the system (Vot) using these values.
Projects designed using earlier versions of ASHRAE 62.1 (2007-2026) may use those VRP design calculations to comply with this credit.
Increased Ventilation for Naturally Ventilated Spaces
For naturally ventilated spaces, increased ventilation requires having larger openings than the minimum opening sizes in ASHRAE 62.1 or having features intentionally designed to provide increased airflow.
REGULARLY OCCUPIED SPACES REQUIREMENT
At least 95% of all regularly occupied spaces must have increased ventilation. This provides flexibility for projects that cannot meet the higher thresholds in every space.
DETERMINING THE INCREASED VENTILATION REQUIREMENT
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Prescriptive System . Demonstrate the opening areas in each naturally ventilated space are larger than the opening sizes required in ASHRAE 62.1 Section 6.4.2.
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Engineered system . Demonstrate through natural ventilation design calculations that expected airflow in the space exceeds the minimum rates outlined in ASHRAE 62.1 by 15% or 30%.
Projects designed using earlier versions of ASHRAE 62.1 (2007-2026) may use those natural ventilation design calculations to comply with this credit.
DOCUMENTATION
| Project types | Options/Paths | Required for upload | Documentation |
|---|---|---|---|
All | Ventilation performance | Calculation | Calculations from_EQp1: Verification of Ventilation_ and Filtration |
REFERENCED STANDARDS
- None
U.S. Green Building Council LEED v5 Reference Guide for Operations and Maintenance, April 2025 Launch Edition 234