In order to find the right calculator divide the attic floor space by 300 sq feet.
Required residential roof vents.
In our case the required 4 vents for the 1200 sq ft.
The roofing industry also has practical guide lines for attic ventilation.
Ventsure 4 foot strip heat moisture ridge vent.
1 cubic foot is 12 x 12 144 cubic inches.
Typically building codes include minimum requirements applicable to attic ventilation.
Soffit vents are one of the most popular intake vent styles.
Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca.
Before we explore how to ventilate an attic space it is prudent to understand how much ventilation is needed.
Effective attic ventilation systems reduce damaging heat and moisture in your attic promote energy efficiency by helping to reduce the load on your air conditioner in the summer and also reduce the risk of ice dam formation on your roof.
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.
Where a roof is used for any purpose other than weather protection vents shall extend at least 7 feet above the roof and shall be properly supported.
27 lineal feet required.
The majority of the requirements related to attic ventilation have not changed much from the previous editions.
Choose one of the following products to meet the recommended exhaust nfva of 528 square inches.
Taking advantage of this natural process referred to as passive ventilation is the most common way to vent an attic.
Vent pipes shall terminate not less than 6 inches above the roof measured from the highest point where the vent intersects the roof.
Continuous or individual soffits.
Code requirements the international building code.
They are easy to install under the roof s overhang which is known as the soffit are generally hidden from sight and provide excellent protection from weather outdoor debris and pests while still allowing air to flow into the attic.
If your roof is 1200 sq ft soffit floor space you will need 4 sq feet of roof ventilation.
The following are the requirements taken directly from the irc.
Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems.
The ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction.
Hot air exhaust vents located at the peak of the roof allow hot air to escape.
See the benefits of attic ventilation a new roof is more than just shingles.
