Attic Ventilation Requirements California

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

Attic ventilation requirements california.

If your attic is enclosed california s building code states it should have cross ventilation. 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. A ridge vent and through roof vents can be seen on the roof of the building shown here. Operable windows are excluded from the options for meeting whole building ventilation requirements.

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. 1203 2 under floor 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. The minimum net free ventilating area shall be 1 150 of the area of the vented space.

The minimum net free ventilation area shall be 1 300 of the vented space provided one or more of the following conditions are met. Vents are vulnerable to wildfires when embers and flames enter into the enclosed attic or crawl spaces and ignite combustible materials in those areas. 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. Ventilation guide 2007 california building code attic ventilation.

Not less than 40 percent and not more than 50. 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. Roof ceiling construction requirements are listed in california residential code chapter 8. California title 24 part 6 references ashrae standard 62 2 2007 as california s state ventilation code with one exception.

This handout is intended to provide the information regarding proper roof ventilation and insulation clearance.