Attic Ventilation Requirements Canada

Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge.

Attic ventilation requirements canada.

Vent requirements 1 except as provided in sentence 2 the unobstructed vent area shall be not less than 1 300 of the insulated ceiling area. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Attic ventilation serves a number of purposes. 2 where the roof slope is less than 1 in 6 or in roofs that are constructed with roof joists the unobstructed vent area shall be not less than 1 150 of the insulated ceiling area.

The following are the requirements taken directly from the irc. Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space. The ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction. Let owens corning roofing help you calculate exactly how much ventilation you will need for a healthy and balanced attic with our 4 step ventilation calculator.

It reduces summer heat buildup prolonging the life of roofing and reduces air conditioner loads. The ontario building code vent requirements 9 19 1 2. It comes on an easy to install flexible mesh roll and is hand nailable with no complicated fitting wrapping nail gun adapters. Careful attention to the need for adequate ventilation is necessary when water and vapour impermeable roof covers are applied over attic and roof spaces.

Intake vents located at the lowest part of the roof under the eaves. Ridge static attic vents 384 00 minimum sq. A ridge vent is a ventilation strip that is placed along the ridgeline of the home. For the 1 150 attic ventilation requirement simply double the amount of exhaust and intake calculated.

It is important that air movement occurs and is not impeded by any framing members of the. Of net free area of exhaust needed at or near the ridge. Of net free area of intake needed at or near the soffit. After air sealing attic ventilation is your second line of defence against the water vapour that may have found its way into the attic.

The majority of the requirements related to attic ventilation have not changed much from the previous editions.