In order to find the right calculator divide the attic floor space by 300 sq feet.
Roof space ventilation.
Intake vents located at the lowest part of the roof under the eaves allow cool.
If you see dampness or frost you need better roof ventilation and some attic vents.
If the attic space is going to be conditioned either for living or mechanical purposes or if a home design calls for a vaulted ceiling provision r806 3 in the international residential code calls for the roof deck above the space to be vented continuously from the eave to the ridge.
To calculate the amount of ventilation you need for your home visit gaf s ventilation calculator now.
An important part of installing any system of ventilation into your roof system is to make sure that there is a point of entry and a point of exit for airflow.
If your roof is 1200 sq ft soffit floor space you will need 4 sq feet of roof ventilation.
Vent the roof deck.
Grab a flashlight and inspect your attic during the winter.
Typically building codes include minimum attic space ventilation requirements as well as the roofing industry weighing in on practical guidelines.
As a homeowner it is important that you review the soffit areas of the home for soffit vents.
The air gap dimensions shown on the drawings are the minimum widths required for clear continuous ventilation air paths at the eaves.
Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.
Ventilation at the eaves roof voids must be ventilated in order to stop warm air condensing on cold surfaces.
There should also be a 50 50 balance of attic venting and roof venting.
Warm air that escapes living space also carries moisture that will condense on rafters or roof sheathing.
For the best results place roof ventilation near the roof s peak and soffit vents in the eaves.
Enclosed attics and enclosed rafter spaces formed where ceilings are applied directly to the underside of roof rafters shall have cross ventilation for each separate space by ventilating openings protected against the entrance of rain or snow.
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 or enter the square footage of the attic or area to be vented.