Roof Attic Ventilation Requirement

You can calculate attic ventilation requirements by determining the square footage of your attic.

Roof attic ventilation requirement.

Effective attic ventilation systems reduce damaging heat and moisture in your attic promote energy efficiency by helping to reduce the load on your air conditioner in the summer and also reduce the risk of ice dam formation on your roof. The ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction. In cold climates the primary purpose of attic or roof ventilation is to maintain a cold roof temperature to control ice dams created by melting snow and to vent moisture that moves from the conditioned space to the attic ventilation acts to bypass the vapour barrier created by most roof. Explore owens corning ventilation products.

Attic ventilation requirements how many attic vents your roof needs industry standard for proper attic ventilation recommends for no vapor retarder type of attic insulation no paper plastic or aluminum layer between the attic floor and insulation layer 1 sq. Typically building codes include minimum requirements applicable to attic ventilation. Intake vents located at the lowest part of the roof under the eaves allow cool. See the benefits of attic ventilation a new roof is more than just shingles.

The following are the requirements taken directly from the irc. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. 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. Foot of ventilation for every 150 sq.

Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems. Code requirements the international building code. The roofing industry also has practical guide lines for attic ventilation. Throughout the balance of this digest the terms attic and roof will and can be used interchangeably.

The majority of the requirements related to attic ventilation have not changed much from the previous editions. 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. The key to proper ventilation of your roof and attic is balance. 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.

Most building codes require a ratio of 1 150 ventilation space to attic floor space. Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca.