Cbc Attic Ventilation Requirements

1 square foot of ventilation for each 150 square feet of attic space.

Cbc attic ventilation requirements. Occupiable spaces listed in table 402 1 shall be designed to have ventilation outdoor air for occupants in accordance with this chapter. 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. That is openings doors windows and louvers to the outside should create a. Code requirements the international building code.

Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems. Foot of ventilation for every 150 sq. Enter square footage calculate or enter the square footage of the attic or area to be vented. Typically building codes include minimum requirements applicable to attic ventilation.

Enclosed attics and enclosed rafter spaces formed where ceilings are applied directly to the underside of roof rafters shall have cross ventilation for each separate space by ventilating openings protected against the entrance of rain or snow. Ventilation air supply requirements for occupancies regulated by the california energy commission are found in the california energy code. Ventilation openings shall have a least dimension of 1 16 inch 1 6 mm minimum and 1 4 inch 6 4 mm maximum. 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. 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. Design requirements for roof top solar panels and references new sections added to asce 7. 1203 3 the uniform building code requires enclosed attic spaces enclosed rafter spaces and under floor areas to be ventilated by not less than 1 square foot for each 150 square feet of attic under floor area.

Amendment also allows dsa. The chart below represents the net minimum area in square inches required for proper ventilation. The net free ventilation shall be a minimum ratio of 1 150 of the area or space ventilated e g. Feet of attic space divided 50 50.

Recognizes current shotcrete references aci 506 213 and aci 506r 16. 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.