How Many Roof Vents Should You Have

Enter square footage calculate or enter the square footage of the attic or area to be vented.

How many roof vents should you have.

Feet of attic space divided 50 50. Taking advantage of this natural process referred to as passive ventilation is the most common way to vent an attic. In of vent opening per 150 sq. With any attic ventilation system the attic can be 20 degrees hotter than outside.

Then aim for about 1 sq. Foot of ventilation for every 150 sq. 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. First determine your attic area by multiplying the length by the width.

Attic ventilation requirements how many attic vents your roof needs. Attic for example has an area of 1 200 sq. 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. If you have a hip roof with very little ridge a power fan with both a thermostat and humidistat for both temperature and humidity should be installed with no ridge vent.

For example if you have 1200 square feet of attic space you should need at least 4 air vents to ensure proper ventilation. Solid vinyl soffit material costs the same as the vented material. Thus if your attic is 450 square feet you need roof vents equaling 3 square feet. As a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space.

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. 8 perform similar calculations for the roof and ridge vents. You ll need the square footage of your attic to calculate the number of roof vents that you should need. Hot air exhaust vents located at the peak of the roof allow hot air to escape.

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. It s important to remember that it s better to have too much intake ventilation than too little and many homes often undercalculate the amount of intake needed so worry less about having too much intake and err on the side of having more. Then you can begin choosing the style and type of roof vents you want for your home.