Attic Ventilation Requirements California

These requirements cover the design and construction of roof ceiling systems including roof framing roof drainage roof sheathing ceiling finishes roof ventilation and attic access.

Attic ventilation requirements california. If your attic is enclosed california s building code states it should have cross ventilation. The minimum net free ventilation area shall be 1 300 of the vented space provided one or more of the following conditions are met. 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. G forms handouts building attic ventilation docx page 1 of 1 a ttic v entilation purpose enclosed attics and enclosed rafters are required by the california residential code to have proper ventilation.

That is openings doors windows and louvers to the outside should create a. Ventilation guide 2007 california building code attic ventilation. 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. Vents are vulnerable to wildfires when embers and flames enter into the enclosed attic or crawl spaces and ignite combustible materials in those areas.

This handout is intended to provide the information regarding proper roof ventilation and insulation clearance. The minimum net free ventilating area shall be 1 150 of the area of the vented space. 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. In climate zones 14 and 16 a class i or ii vapor retarder is installed on the warm in winter side of the ceiling.

Not less than 40 percent and not more than 50. Operable windows are excluded from the options for meeting whole building ventilation requirements. 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. 1203 2 under floor ventilation.

A strip vent in a soffited eave and frieze block vents in an open framed eave are shown here.