2009 Irc Roof Ventilation Requirements

The ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction.

2009 irc roof ventilation requirements.

The majority of the requirements related to attic ventilation have not changed much from the previous editions. January 2009 code for residential buildings that creates minimum regulations for one and two family dwellings of three stories or less. 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 roofing industry also has practical guide lines for attic ventilation.

Ventilation openings shall have a least dimension of 1 16 inch 1 6 mm minimum and 1 4 inch 6 4 mm maximum. Where the roof sheathing is less than 3 4 inch 19 1 mm thick the nails. For impact rated fenestration complying with section r301 2 1 2 of the irc or section 1608 1 2 of the ibc maximum u factor shall be 0 75 in zone 2 and 0 65 in zone 3. Where the roof sheathing is less than 3 4 inch 19 mm thick the.

Between half and two thirds of the provided ventilation shall be installed at the eaves. It brings together all building plumbing mechanical fuel gas energy and electrical provisions for one and two family residences. The ventilation openings shall have a least dimension of 1 16 inch 1 6 mm minimum and 1 4 inch 6 4 mm maximum. Open vent pipes that extend through a roof shall be terminated at least 6 inches 152 mm above the roof or 6 inches 152 mm above the anticipated snow accumulation whichever is greater except that where a roof is to be used for any purpose other than weather protection the vent extension shall be run at least 7 feet 2134 mm above the roof.

U factor and total ua res check approach. 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. Vented attics shall have a minimum net free ventilation area at least 1 300 of the area of the vented space. Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems.

The following are the requirements taken directly from the irc. Fasteners for asphalt shingles shall be galvanized steel stainless steel aluminum or copper roofing nails minimum 12 gage 0 105 inch 3 mm shank with a minimum 3 8 inch 10 mm diameter head astm f 1667 of a length to penetrate through the roofing materials and a minimum of 3 4 inch 19 mm into the roof sheathing.