Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.
Design attic ventilation.
Soffit vents may leave air trapped at the top of your attic.
The model building codes allow both vented and unvented roof assemblies.
Static roof line vents are effective for ventilation but generally aren t recommended due to issues with leaks.
Traditional design better attic venting is achieved with continuous soffit intake and ridge outlet venting.
If you see dampness or frost you need better roof ventilation and some attic vents.
Enter square footage calculate or enter the square footage of the attic or area to be vented.
Air flows in through the soffit vents and out through the roof vents.
The first is the air entering through the circular soffit vents that incorporate a wire mesh referred to as bird blocks moreover there are other popular soffit vent styles including perforated lots or panels below the soffit.
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.
Get started indoor air quality iaq poor indoor air quality can have a negative effect on your home.
Also see insulation air heat leaks.
These ventilation needs are calculated differently.
The choice of venting or not venting is a design and construction choice not a requirement determined by the physics or by the building code.
There are some styles of vaulted ceiling homes or flat roof homes that have ventilation spaces within the roof itself and no attic.
Grab a flashlight and inspect your attic during the winter.
Most building codes require a ratio of 1 150 ventilation space to attic floor space.
Properly venting the attic ventilation is often a challenging task and it entails two processes.
Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca.
Most effective ventilation uses a ridge and soffit continuous ventilation system but even these designs can vary from roof to roof.
Add continuous soffit vents at the eaves.
Attic ventilation estimating tool.
The amount of space you devote to intake must be equal to the amount you allow for exhaust and these must be calculated according to the size of your attic and slope of your roof.
You can also contact your local municipality to check on building code in your area.
The key to proper ventilation of your roof and attic is balance.
Use this tool to estimate the ventilation needs for your attic and get a list of broan attic ventilation product that will meet your needs.
Hot air exhaust vents located at the peak of the roof allow hot air to escape.
Replacing your bathroom fan range hood or even installing a new fan.
Attics or roofs can be designed and constructed to be either vented or unvented in any hygro thermal zone map 1.