Attic Ventilation Requirements Canada

The following are the requirements taken directly from the irc.

Attic ventilation requirements canada.

Intake vents located at the lowest part of the roof under the eaves. The ontario building code vent requirements 9 19 1 2. Heat build up the canadian asphalt shingle manufacturers association has issued a bulletin titled proper ventilation for asphalt shingle covered roofs. 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.

Ridge static attic vents 384 00 minimum sq. It is important that air movement occurs and is not impeded by any framing members of the. 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. 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.

A ridge vent is a ventilation strip that is placed along the ridgeline of the home. 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. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. The majority of the requirements related to attic ventilation have not changed much from the previous editions.

When installed as part of a properly balanced when installed as part of a properly balanced attic ventilation system gaf cobra exhaust vent is a shingle over exhaust vent installed at the roof ridge that helps exhaust excess heat and moisture from your attic. It reduces summer heat buildup prolonging the life of roofing and reduces air conditioner loads. The ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction. After air sealing attic ventilation is your second line of defence against the water vapour that may have found its way into the attic.

Prior to installing the ridge vent a 1 inch wide strip of roof decking is cut out along both sides of the ridgeline to allow for air movement through the vent. Of net free area of exhaust needed at or near the ridge. For the 1 150 attic ventilation requirement simply double the amount of exhaust and intake calculated. Of net free area of intake needed at or near the soffit.

Careful attention to the need for adequate ventilation is necessary when water and vapour impermeable roof covers are applied over attic and roof spaces.