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.
Attic ventilation requirements calculator.
Gaf attic ventilation calculator.
If your roof is 1200 sq ft soffit floor space you will need 4 sq feet of roof ventilation.
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.
The ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction.
The following are the requirements taken directly from the irc.
Roof ventilation calculator enter your attic area or length and width to determine your ventilation needs.
Calculate the total vent area needed.
Width or area.
Home attic vent calculator for years we have been working with architects and specifiers to ensure affordable roof ventilation that upholds building code standards.
Result of item 1 300.
The majority of the requirements related to attic ventilation have not changed much from the previous editions.
Calculating attic ventilation requirements.
Use this calculator to help determine the proper amount of attic ventilation based on u s.
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.
Calculate the square footage of the attic space.
The two square feet is divided equally between the intake and the exhaust one square foot for each.
Select ventilation product flex roll ridge vent multi roll multi purpose vent rigid roll ridge.
In order to find the right calculator divide the attic floor.
Length x width of attic in feet 150 total sq.
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.
A 50 x 30 attic would have a total area of 1 500 sq.
Vent calculator design your balanced ventilation system.
There should also be a 50 50 balance of attic venting and roof venting.
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.
Our passive roof vents are ul certified and rated to withstand wind pressure in excess of 200 mph.
Of total 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.
Divide the square footage item 1 by 300.