Ventilation Requirements for LEED Compliance

LEED: IEQ Prerequisite

    The Indoor Environmental Quality (EQ) category rewards decisions made by project teams about indoor air quality<br />and thermal, visual, and acoustic comfort. Green buildings with good indoor environmental quality protect the<br />health and comfort of building occupants. High-quality indoor environments also enhance productivity, decrease<br />absenteeism, improve the building’s value, and reduce liability for building designers and owners.</p>      
        <h5>IEQ Mininum Indoor Air Quality performance</h5>     
    <p>INTENT<br />To contribute to the comfort and well-being of building occupants by establishing minimum standards for indoor air quality (IAQ).

REQUIREMENTS

Meet the requirements for both ventilation and monitoring.

Mechanically Ventilated spaces

Option 1: ASHRAE Standard 62.1–2010

Maintain the ventilation system equipment and associated components based on Table 8.2 of ASHRAE 62.1-2016. Include information on ventilation system operation and preventative maintenance in the current facilities requirements and operations and maintenance plan required for compliance with EA prerequisite Energy Efficiency Best Management Practices.

ASHRAE 62.1-2010

Breathing Zone Outdoor Airflow.

The outdoor airflow required in the breathing zone of the occupiable space or spaces in a ventilation zone, i.e., the breathing zone outdoor airflow (Vbz), shall be no less than the value determined in accordance with Equation 6-1.

Vbz = Rp · Pz + Ra · Az

where
Az = zone floor area: the net occupiable floor area of the ventilation zone ft2 (m2)
Pz = zone population: the number of people in the ventilation zone during typical usage.
Rp = outdoor airflow rate required per person as determined from Table 6-1
Note: These values are based on adapted occupants.
Ra = outdoor airflow rate required per unit area as determined from Table 6-1

 Full table can be accessed in ASHRAE 62.1, Table 6-1, Page- 15

Table 6-2 & Table 6-3 for Ez and Ev values from Ashrae 62.1-2010

For any multiple-zone recirculating system, the system ventilation efficiency (Ev) shall be calculated in accordance with Sections A1.1 through A1.3 from ASHRAE 62.1-2010.

Example: Reference Project

Given below is a reference project with its LEED IEQ- Min indoor air quality performance calculator. The indoor air requirements of all conditioned spaces are calculated floor wise.

The outdoor intake air  should be equal to or less than the base case that is calculated as per ASHRAE 62.1.

Input Values in the LEED Min indoor air quality calculator, e.g, Zones, zone area, Zone air distribution per person and per sq. ft area.

Output values: Outdoor air intake flow (as per ASHRAE 62.1) is calculated and the provided outdoor air intake is input.

Final Output: After putting values floorwise, a final summary table is generated which compares the provided outdoor air intake flow to the base-case (as per 62.1). It should either be equal to or greater than the base-case.