The 2 Types of Attic Ventilation Systems (& Their Types of Roof Vents)
When you think about your roof, you probably don’t think about your attic. But the truth is, your attic’s ventilation system is crucial to your roof and even your home.
Poor attic ventilation could even be the cause of your high energy bills in the summer. That’s why every homeowner needs to understand the importance of a properly working ventilation system.
That all starts with learning the 2 types of attic ventilation systems. Because we want you to be the most informed homeowner in your neighborhood, we’re going to break it down for you.
Since 1990, the team at Bill Ragan Roofing has helped the residents of Nashville deal with attic ventilation problems. We always explain to homeowners how attic ventilation impacts both their roof and home. Because of its importance, one of the first things we look for during an inspection is if your attic is properly ventilated.
By the end of this article, you’ll learn the 2 types of attic ventilation systems and the roof vent options for each type.
The 2 types of attic ventilation systems
Your attic’s ventilation is a system that allows your house to breathe. Without proper attic ventilation, your roof’s life will be cut short and your energy bills will be high.
There are 2 types of attic ventilation systems: active and passive. Your attic’s ventilation works by pulling fresh air through your attic and allowing the heat to escape through your vents properly.
Both types of ventilation systems do their job, and one isn’t better than the other. However, they function differently and have different types of roof vents that help them do the job.
Active attic ventilation system
Active ventilation pulls fresh air in from the outside and pushes the air in your attic out from the inside. It works by creating a drawing effect when the intake vents pull fresh air from the outside and pushes the air in your attic out through the exhaust vents.
Unlike passive ventilation, this system and its vents are actively working to ensure the air in your attic is moved around correctly. The 4 common types of active roof vents: turbine, power, ridge, and solar-powered vents.
Turbine vents (also known as whirly birds) work by using a drawing effect through convection (heat rising) to move the air in your attic around even when there is no wind.
As long as this type of vent is installed properly, the air in your attic is moved around 10-12 times per hour.
Because turbine vents have slats on them and are open-aired to the attic, there is a misconception that rain, snow, and insects can enter your home through them. However, they’re designed so that none of this occurs unless the vent is damaged.
Power vents are circular-shaped vents with very low profiles you see on most roofs.
They’re installed near the ridge (top) of the roof and use electricity to pull the hot air from the attic. During the winter, you’ll want to run your power vents with a humidistat.
Otherwise, the humidity will build up in your attic, cause condensation, and shorten your roof’s lifespan. Be aware, power vent motors tend to fail, so be prepared to replace them at some point.
Ridge vent with a baffle
Ridge vents are cut into the ridge of the roof and run the entire length of it.
This style of vent is popular because they aren’t noticeable from the ground. While they’re extremely popular, the downside to this vent is that if the vent doesn't have a filter, insects, debris, rain, and snow can enter the attic.
If a ridge vent doesn’t have a baffle (chutes that provide a channel for air to flow) to help move the air through your attic, then it’s a passive vent.
Solar-powered vents are like power vents, but they use the sun as their power source.
These vents sound great from an energy saver standpoint, but the vent turns off when the solar-powered battery is charging.
The problem is that the solar panel won’t hold a charge long enough to run the vent all day due to the power needed to run the motor. So while the battery is recharging, you may wind up with your air conditioner running more, which will cause your energy bill to go up.
Passive attic ventilation system
Passive ventilation works by letting the air in the attic be moved around by natural sources. Unlike active ventilation, this system doesn’t rely on the vents themselves to ensure the trapped air is able to escape.
Passive ventilation relies on wind or convection (the cool air pushes the warm air out) to move the air in your attic around properly. The common types of passive roof vents are static, ridge vents without a baffle, and gable end vents. These vents have no moving parts, create no noise, and are virtually maintenance-free.
Static vents look like little boxes on your roof.
They work by allowing the heat to escape out of the roof through the convection method.
This means as the heat in your attic rises, the hot air is pushed out through the vents. You might also hear static vents called turtle vents or box vents.
Ridge vents without a baffle
Like the active version of this type of roof vent, it’s cut into the ridge and runs the entire length of the ridge.
The only difference is that there’s no baffle (chutes that provide a channel for air to flow). The problem with ridge vents without a baffle is that it allows debris, rain, snow, insects, etc. to enter your attic.
Gable end vents
A gable end vent is a wooden vent installed on the exterior wall of your attic below where the 2 slopes of your roof meet. This vent relies on the wind coming from the outside to move the air in and out of your attic.
Why is proper attic ventilation important?
Now you know the 2 types of attic ventilation systems and the common types of roof vents. Remember, one ventilation system isn’t better than the other.
No matter which one you have, the most important thing is that your attic ventilation system is working properly. If it isn’t, it’s going to cause problems with your roof and even your home.
That’s why every homeowner needs to know why proper attic ventilation is important. Because of its importance, we already broke it down for you in another article.
The team at Bill Ragan Roofing has provided high-quality roofing services in Nashville and surrounding areas since 1990. No matter if you need your attic’s ventilation inspected, roof repairs, or a full roof replacement, you can count on us. If you’re local to Nashville, don’t hesitate to contact us for any of your roofing needs.
To learn why your attic’s ventilation system is crucial, check out this article on 3 Reasons Why Proper Attic Ventilation Is Important to Your Roof and Home.