How Many Roof Vents Do You Need

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.

How many roof vents do you need.

General rule of thumb is 1 whirlybird for every 50m2 of roof void space. This means that you should add more roof vents than 1 per 150 square feet. Choosing round soffit vents for this home means that 8 square feet of required ventilation be divided by 0 196 for about 40 round vents. 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.

For example if you have 1200 square feet of attic space you should need at least 4 air vents to ensure proper ventilation. For published install prices in sydney click here average example is for a 2 3 bedroom house you ll need approximately 2 roof vents. Use the calculator below to find out how many exhaust and intake vents you will need on your house. 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.

Foot of ventilation for every 150 sq. Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation for every 300 square feet of attic floor space evenly split between intake and exhaust. But if your roof has a slope greater than 6 12 this means that there will be more volume in your attic than the actual square footage. For a 3 4 bedroom house 3 roof vents and for a 4 5 bedroom house 4 roof vents.

Feet of attic space divided 50 50 between the inlets and outlets. Rafter vents or insulation baffles install in any rafter space to create narrow gaps that direct fresh air from the soffit vents to the peak of the roof. As a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space. Thus if your attic is 450 square feet you need roof vents equaling 3 square feet.

If you want to learn more or are interested in a roofing job 1 800 hansons is at your service. 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. Roofing resources during covid 19 for contractors for homeowners. You ll need the square footage of your attic to calculate the number of roof vents that you should need.

You should provide an equal distribution between intake and exhaust vents. How many roof vents do i need. These specialty vents do not affect the.