Commercial Bathroom Exhaust Fan Code Requirements

According to the code this circuit may be a 15 amp circuit if it serves just lighting but it should be a 20 amp circuit if it is also serving a vent fan.

Commercial bathroom exhaust fan code requirements.

This exhaust air can be routed either to the roof using ductwork and a roof vent or to the side of your building using ductwork and a hooded wall vent. Local exhaust systems shall be provided in kitchens bathrooms and toilet rooms and shall have the capacity to exhaust the minimum airflow rate determined in accordance with table 403 3 2 3. 50 cfm intermittent or 20 cfm continuous operation 2006 irc 303 3x. 25 or 50 cfm ft for hotels motels resorts and dormitories and a slightly more modest 20 50 cfm for private dwellings.

Bathrooms must have windows when this section is adopted by a community it essentially says that for venting purposes bathrooms must have windows that open. Bathroom exhaust fan venting code summary section r303 3. The illustration above demonstrates the use of a ceiling exhaust fan mounted in the rest room exhausting the stale air. Every occupied space shall be ventilated by natural means in accordance with section 402 or by mechanical means in accordance with section 403.

Air inlets must be at least 10 feet with exceptions from known contaminant sources and protected from snow with rodents and insect screens. 1 cubic foot per minute 0 0004719 m 3 s. Every bathroom requires an openable window that provides at least 1 5 square ft of air flow area when open 2006 irc 303 3 or mechanical type ventilation. In lieu of compliance with section 403 1 through section 403 3 mechanical ventilation may be implemented in compli ance with ashrae 62 1.

Spaces meeting exhaust requirements of bathrooms are exempted from above provisions. The exhaust from a bathroom or kitchen in a residential dwelling shall not be considered to be a hazardous or noxious contaminant. This ventilation code specifies a bathroom exhaust airflow rate for toilet rooms and bathrooms not served by a window of adequate size of. Each bathroom should have a circuit for lighting and an exhaust fan.

Table 403 3 2 3 minimum required local exhaust rates for group r 2 r 3 and r 4 occupancies for si. Required bathroom vent fan ventilation rate in cfm.