Attic Space Venting Requirements

The following product options will allow you to achieve an intake nfva of 528 square inches.

Attic space venting requirements.

Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. If the attic is equipped with high and low ventilation openings the requirement is 1. There should also be a 50 50 balance of attic venting and roof venting. Allows cool dry air to enter the attic.

So the decision to vent an attic space is not dictated by building code. Hence you would need two square feet 600 300 of attic ventilation. The following is a list of options for installing ventilation into a residential attic space. In order to find the right calculator divide the attic floor.

Calculating attic ventilation requirements. Code requirements the international building code. 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. Intake vents located at the lowest part of the roof under the eaves allow cool.

Attics must have a minimum of 1 square foot of ventilation openings for every 150 square feet of floor space. Building codes typically require 1 square foot of venting space for every 150 square feet of attic space. A ridge vent is a ventilation strip that is placed along the ridgeline of the home. 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.

It really is a design choice. Calculate the square footage of the attic space. If your roof is 1200 sq ft soffit floor space you will need 4 sq feet of roof ventilation. The two square feet is divided equally between the intake and the exhaust one square foot for each.

Choose one of the following products to meet the recommended intake nfva of 528 square inches. According to their requirements you should have 1 square foot of attic ventilation per 300 sq ft of attic floor space. The venting space should be equally divided between intake. Divide the square footage item 1 by 300.

Typically building codes include minimum requirements applicable to attic ventilation. Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems. Result of item 1 300. 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.

The roofing industry also has practical guide lines for attic ventilation.