A lot of humid air is built up in the home with cooking, washing, and even showering. As this moist air condenses, it wets your insulation and framing, leading to the formation of mildew, mold and rot. Installing attic ventilation protects your home from these damages. There are two major categories of attic vents:

Intake Vents

Intake vents are vents designed to let air enter into your attic. They are placed along the soffit to good effect. There are different type of intake vents.

• Soffit vents: These type of vents consist of an aluminum panel and louvers to allow air flow. They are fitted in rectangular holes cut into the attic, and with a screen that prevents insects from also gaining access into the attic.
• Gable vents: These are triangular intake vents installed right below the roof’s peak.
• Static vents: These are metal cylinders with a hood and a flashing collar to keep rain out. To install, rows of holes are cut along the roof’s face, and the vents’ flashing collars are nailed to the roof sheathing. They are also known as roof line vents.

Exhaust Vents

Exhaust vents are vents designed to let air escape from the attic, and are installed in the upper third of the roof for efficiency. There are also different types of exhaust vents.

• Ridge vents: These are static exhaust vents installed along the roof’s peak.
• Turbine vents: Consisting a turbine, they are mounted on a cylinder and installed along the face of the roof. When the wind blows, the turbine spins and air is drawn out of the attic.
• Power vents: These vents are powered by electricity, driven by fans, and controlled by a thermostat installed in your attic (usually a part of the unit).

Attic Ventilation Tips

An attic ventilation system is installed with one goal in mind – creating a continuous current of air in the attic, along the underside of your roof sheathing. This would require varying number of vents for different homes, depending on the size of your attic and the type of vents you use and their sizes. Attic vents ratings are dependent on the amount of open space in the vent, but this is not so easy to calculate. As a rule of thumb, try to strike a balance between intake and exhaust by allocating a minimum of 1 sq. ft. of ventilation per 300 sq. ft. of attic space.

With the number of vents determined, it is time to consider positioning. Installing vents in the middle of your roof can disrupt the natural flow of air. Thus, vents are best installed evenly along the roof, with half placed near the ridge and the other half placed near the soffits or eaves. Keep debris and insulation away from the vents to allow them enough room for air intake and exhaust, and prevent possible blockages.

Now that you have a basic understanding of the different types of attic vents, contact us at 4 Weather Ventilation & Insulation to take a look at your home and see if any improvements can be made.