Mechanical ventilation system fans shall meet the efficacy requirements of Table R403.5.1.
MECHANICAL VENTILATION SYSTEM FAN EFFICACY
|FAN LOCATION||AIR FLOW RATE MINIMUM |
|MINIMUM EFFICACY |
|AIR FLOW RATE MAXIMUM |
|Range hoods||Any||2.8 cfm/watt||Any|
|In-line fan||Any||2.8 cfm/watt||Any|
|Bathroom, utility room||10||1.4 cfm/watt||< 90|
|Bathroom, utility room||90||2.8 cfm/watt||Any|
Residential buildings designed to be operated at a positive indoor pressure or for mechanical ventilation shall meet the following criteria:
- The design air change per hour minimums for residential buildings in ASHRAE 62, Ventilation for Acceptable Indoor Air Quality, shall be the maximum rates allowed for residential applications.
- No ventilation or air-conditioning system make-up air shall be provided to conditioned space from attics, crawlspaces, attached enclosed garages or outdoor spaces adjacent to swimming pools or spas.
- If ventilation air is drawn from enclosed space(s), then the walls of the space(s) from which air is drawn shall be insulated to a minimum of R-11 and the ceiling shall be insulated to a minimum of R-19, space permitting, or R-10 otherwise.