Calculating Attic Ventilation Needs

Use this calculator to help determine the proper amount of attic ventilation based on u s.

Calculating attic ventilation needs.

Let s use the following simple ranch house for an example. Hence you would need two square feet 600 300 of attic ventilation. Of total vent space needed. Standard attic vents like af 50 s ventilation fans or solar powered attic fans.

For balanced ventilation an equal amount of intake vent area net free area should also be installed. His home is 48 feet long and has a ridge vent that measures 46 feet. Calculating ventilation area of attic kitchen ventilation text. 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.

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. Ft divided by 150 equals 10 sq. Calculate the square footage of the attic space. The house measures 30 feet by 50 feet.

Ridge vents are one of the easiest ways to meet roof venting requirements. Calculating attic ventilation requirements. How attic ventilation works. Use avp s roof vent calculator to determine the number and size of exhaust vents you will need.

Calculate the total vent area needed. The ridge vent is cut back 1 inch on either side of the ridgeline which yields a total area of 7 67 square feet of ventilation. Intake vents located at the lowest part of the roof. The two square feet is divided equally between the intake and the exhaust one square foot for each.

Result of item 1 300. Multiply the length of the attic times the width in feet to find the attic area then divide by 150 to find the total square feet of vent space needed. 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. Gaf attic ventilation calculator.

A 50 x 30 attic would have a total area of 1 500 sq. Enter square footage calculate or enter the square footage of the attic or area to be vented. Length x width of attic in feet 150 total sq. His next step is to calculate the total amount of ventilation that he has in his attic.

Divide the square footage item 1 by 300. Other options to meet your attic ventilation needs are. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.