Artificial Ventilation Requirements

Ventilation Requirements

• Rooms with industrial or heating equipment must have artificial ventilation to prevent excessive accumulation of hot and/or polluted air.
• Artificial ventilation systems must meet minimum requirements, including:
  • 3 changes of air per hour for offices, clerical, or administrative spaces above grade.
  • 10 changes of air per hour for bakeries, kitchens, laundries, and boiler rooms above grade.
  • 0.03 cubic meter of air per minute per person for auditoriums and assembly rooms.
  • 0.45 cubic meter of air per minute per person for wards and dormitories in institutional buildings.

Vent Shafts

• Ventilation or vent shafts must have a horizontal cross-sectional area of at least 0.10 square meter per meter of height, but not less than 1.00 square meter.
• No vent shaft shall have its least dimension less than 600 millimeters.

Skylights and Air Ducts

• Skylights must have a net free area or fixed louver openings equal to the maximum required shaft area.
• Air ducts must open to a street or court by a horizontal duct or intake at a point below the lowest window opening, with a minimum unobstructed cross-sectional area of 0.30 square meter and a minimum dimension of 300 millimeters.

Ventilation Skylights

• Skylights must have a glass area not less than that required for the windows that are replaced.

Enclosed Attic Spaces

• Enclosed attic spaces of combustible construction must be divided into horizontal areas not exceeding 250 square meters by fire-resistive partitions extending from the ceiling to the roof.
• Openings in the partitions must be protected by self-closing doors.

Draft Stops

• Draft stops must be installed in trusses roofs, between roof and bottom chords or trusses, in all buildings exceeding 2000 square meters.

Ventilation for Attics

• Enclosed attics, including rafter spaces, must be provided with adequate ventilation protected against the entrance of rain.

Roof Drainage System

• Roof drains must be installed at low points of the roof and must be adequate in size to discharge all tributary waters.
• Overflow drains and scuppers must be provided where roof drains are required.
• Concealed roofing and overflow drains must be installed in accordance with the National Plumbing Code.