Calculating Attic Ventalation

For balanced ventilation an equal amount of intake vent area net free area should also be installed.

Calculating attic ventalation.

Divide the square footage item 1 by 300. Calculate the square footage of the attic space. Enter the length and width of the attic floor or the total square footage of the attic floor. According to their requirements you should have 1 square foot of attic ventilation per 300 sq ft of attic floor space.

Determine the amount of ventilation needed for your home with this formula. Our soffit vents round back vents pop vents and universal vents make excellent intake 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. Width or area.

Calculate the area of your attic and the proper number of vents. All lomanco attic ventilation product requirements are based on the minimum standard 1 300 rule as set forth by the international building code ibc and the international residential code irc. Calculate the total vent area needed. Select ventilation product flex roll ridge vent multi roll multi purpose vent rigid roll ridge.

Hit the calculate button for the recommended amount of exhaust and intake ventilation. Enter square footage calculate or enter the square footage of the attic or area to be vented. Calculate the square footage of your attic and provide proper attic ventilation with the right number of roof vents ridge vents or soffit vents. If local code requires the 1 150 rule please double the requirements.

There should also be a 50 50 balance of attic venting and roof venting. 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. If your roof is 1200 sq ft soffit floor space you will need 4 sq feet of roof ventilation. Roof ventilation calculator enter your attic area or length and width to determine your ventilation needs.

Length x width of attic in feet 150 total sq. 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. Calculating attic ventilation requirements. Use avp s roof vent calculator to determine the number and size of exhaust vents you will need.

Result of item 1 300.