855773644-LEED-v5-BD-C-Reference-Guide-Launch-Edition - Page 474

Extracted Content

• Systems tested for effectiveness and safety per ASHRAE Standard 241-2023, Section 7.4 (and Normative Appendix A). If treating for particles and gases, use systems tested for effectiveness per ASHRAE 62.1-202 2, Addendum N. If treating for infectious aerosols, use systems tested for effectiveness per A SHRAE Standard 241-2023, Section 7.

• Outdoor air measurement . Provide outdoor airflow measurement devices for all mechanical ventilation systems with outdoor air intake flow greater than 1,000 cfm (472 L/s).

Healthcare

• For healthcare spaces, meet the requirements of Sections 6–10 of ASHRAE Standard 170- 2021 .

Residential

• For residential spaces, follow the additional dwelling unit provisions below.

Dwelling Unit Provisions If the project building contains residential units, each dwelling unit must meet all of the following requirements:

• Design and install a dwelling-unit mechanical ventilation system that complies with ASHRAE 62.2-2022, Sections 4, 6.6, and 6.7. Supply and balanced mechanical ventilation systems must be designed and constructed to provide ventilation air directly from the outdoors. Mechanical ventilation systems are not required when the project meets the exception detailed in ASHRAE 62.2-2022, Section 4.1.1.

• Design and install local mechanical exhaust systems in each kitchen and bathroom, including half baths, that comply with ASHRAE 62.2-2022, Sections 5 and 7. Exhaust air to the outdoors. Do not route exhaust ducts to terminate in attics or interstitial spaces. Recirculating range hoods or recirculating over-the-range microwaves do not satisfy the kitchen exhaust requirements. For exhaust hood systems capable of exhausting in excess of 400 cubic feet per minute (188 liters per second), provide makeup air at a rate approximately equal to the exhaust air rate. Makeup air systems must have a means of closure and be automatically controlled to start and operate simultaneously with the exhaust system. Use ENERGY STAR® labeled bathroom exhaust fans in all bathrooms (including half baths) or performance equivalent for projects outside the U.S. A heat recovery ventilator (HRV) or energy recovery ventilator (ERV) may be used to exhaust single or multiple bathrooms if it has an efficacy level meeting the ENERGY STAR® Technical Specifications for Residential Heat-Recovery Ventilators and Energy-Recovery Ventilators (H/ERVs), version 2.3 as certified by the Home Ventilating Institute.

• Unvented combustion appliances (ovens and ranges excluded) are not allowed.

U.S. Green Building Council LEED v5 Reference Guide for Building Design and Construction, April 2025 Launch Edition 464