Attic Ventilation Requirements Ontario

The amount of space you devote to intake must be equal to the amount you allow for exhaust and these must be calculated according to the size of your attic and slope of your roof.

Attic ventilation requirements ontario.

Of net free area of exhaust needed at or near the ridge. Intake vents located at the lowest part of the roof under the eaves allow cool. Bathrooms can only benefit from some type of exhaust venting system but which type do you need and what does the bathroom exhaust fan venting. 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.

Code requirements the international building code. For minimum building code requirements use the 1 300 ratio instead of the 1 150 ratio. Typically building codes include minimum requirements applicable to attic ventilation. The key to proper ventilation of your roof and attic is balance.

The roofing industry also has practical guide lines for attic ventilation. Of net free area of intake needed at or near the soffit. Bathrooms are wet smelly places that often are closed in and unventilated. Ridge static attic vents 384 00 minimum sq.

You can calculate attic ventilation requirements by determining the square footage of your attic. As ventilation rates vary with wind speed and direction the magnitude of natural ventilation is difficult to predict. Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems. 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.

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. However in canada the largest contributor to infiltration is the temperature difference between the inside of the house and the outside causing in a phenomenon called stack effect. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. For the 1 150 attic ventilation requirement simply double the amount of exhaust and intake calculated.

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. Air vent recommends 1 square foot of ventilation for every 150 square feet of attic floor space with half the ventilation represented by intake vents and half by exhaust vents such as ridge vents. Smells are merely an annoyance.