Roof Vents Per Square Foot

And this guideline you ll need a minimum of.

Roof vents per square foot.

But what happens if we choose to use those individual metal pot vents instead. Our roof is 50 feet long so using a standard product we will get 900 square inches of ventilating space. Based on your 1100 sq. The federal housing administration recommends 1 square foot of attic ventilation for every 150 square feet of attic space.

So the ridge ventilation has exceeded the minimum requirement. Standard ridge vent produces 18 square inches of ventilating area per lineal foot. Building codes typically echo the administration s guidelines. 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.

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. They should be divided equally between inlet and outlet vents and they can be used in any combination that will work with your roof s design. Thus if your attic is 450 square feet you need roof vents equaling 3 square feet. Nine hundred square inches equals 6 25 square feet.

As a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space. The calculations before indicated that we needed 2 square feet of ridge or upper roof ventilation. This formula is traditionally used for static roof vents which are rated for net free area in terms of square inches. 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.

1 square foot of ventilation for every 300 square feet of space for pitched roofs with vapor barriers 1 square foot of ventilation for every 150 square feet of space no vapor barrier and for some municipalities in hot climates. Near ridge of the roof. This means that for every 300 square feet of enclosed attic space 1 square foot of ventilation is required with half at the upper portion exhaust vents and half in the lower portion intake vents.