Most effective ventilation uses a ridge and soffit continuous ventilation system but even these designs can vary from roof to roof.
Design attic ventilation.
In the winter warm moist air seeps into the attic from the living space below.
That keeps your attic dry and reduces ice dams.
Of attic floor space.
A ridge vent is a ventilation strip that is placed along the ridgeline of the home.
The installation of roof vents is a crucial part of roof design because it allows for proper attic ventilation which may help prevent condensation and early aging of your roofing materials.
This means for every 150 square feet of attic floor space there should be 1 square foot of net free area.
See the benefits of attic ventilation a new roof is more than just shingles.
Advantages of proper roofing ventilation.
Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.
If you don t know how your roof vents work or if you re unsure about your attic ventilation in general you should talk to a roof inspector about your current system and any inherent weaknesses that may be at.
Enter square footage calculate or enter the square footage of the attic or area to be vented.
These attic or roof ventilation recommendations are based on a survey of building science literature combined with 40 years of building inspections on the observation of the locations of moisture mold ice dams condensation stains and other clues in buildings and on the correlation of.
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.
Unvented design unvented attic design falls into two categories.
Good ventilation allows the heat and moisture to escape.
Of net free area for every 150 sq.
With vented attic assemblies moisture that diffuses into the attic space from the conditioned space is vented to the exterior by attic ventilation.
Intake vents located at the lowest part of the roof under the eaves allow cool.
Prior to installing the ridge vent a 1 inch wide strip of roof decking is cut out along both sides of the ridgeline to allow for air movement through the vent.
The code minimum for attic ventilation in the 2012 irc section r806 roof ventilation 1 is as follows.
It is important that air movement occurs and is not impeded by any framing members of the.
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.
Roof ventilation choices design specifications.
