How Many Soffit Vents In Attic

Measure your attic the building requirements will probably tell you to place a certain number of soffit vents per square foot of ceiling space.

How many soffit vents in attic.

So a house with a 1 500 sq ft. Almost all homes are fitted with some kind of roof vents at the peak of the roofline be it individual roof vents hip roof ventilation and many homes have gable vents as well. 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. In the article above it says the totalvent area for an attic should equal one square foot of vent space for every 150 square feet of attic area.

This ratio is required for modern insulated homes. For the number of soffit vents in the example divide 8 square feet of ventilation needed by 0 5 for the number of rectangular vents required 16 in the example. Divide the square footage by 150 to calculate the area of ventilation needed since you need 1 square foot of vent space for each 150 square feet of attic space. Attic will need 10 sq.

Of venting ideally about half placed high on the roof and half in the soffits. An attic s intake vents are most commonly installed directly in the soffit either as individual vents spaced every few feet or as one continuous perforated soffit running the entire length of the. Most building codes require 1 sq. Of venting technically net free vent area or nfva for each 150 sq.

In some circumstances you can have less but we recommend the 1 150 ratio. Soffit vents help increase the airflow are easy to install and only cost about 3 per 8 ft. That number is then divided by 2 so that half 1 300 of the vent area is in the soffit vents and half 1 300 is in the ridge vents which is what is called for in r806 2. For example you might have to place one soffit vent and one other kind of vent for each 150 sq.

The ideal roof attic ventilation would consists of combination of vents located in upper section of the attic ridge vents turbine box shaped or dome static vents electric motor powered vents vents installed along the bottom parts of the roof overhang called intake or soffit vents hip vents and or gable vents all of the provided. Enter square footage calculate or enter the square footage of the attic or area to be vented. If you have 3 000 square feet of attic space this equates to 20 square feet of ventilation needed.