You should install a vent on your roof if you want to improve your attic ventilation.
This might not seem like something you should worry about, but if your attic is releasing hot air it can cause problems with your roof.
Poor attic ventilation also increases your energy bills because your air-conditioning system will have to work harder to keep your home at a comfortable temperature.
What’s a roof vent, exactly?
A roof vent is a unit that gets installed on your roof to improve your attic’s ventilation. This makes your roof less likely to experience damage in the form of moisture accumulation or ice dams that can damage its structure.
With that in mind, let’s explore the different types of roof vents and how they work. We’ll start by looking at the two broad categories of roof ventilation systems so you can get a better idea of which one will be better for your home.
Two Broad Categories Of Ventilation
There are two main categories of roof ventilation. These are:
Exhaust vents. If hot air remains inside the home, it can cause mold, mildew, and discomfort during the hot months. Since hot air rises, this is why exhaust-style vents are installed close to the top of the roof line.
Intake vents. While removing hot air from your attic is good, you have to force it out with cool air. Intake ventilation is when you bring fresh air into the attic to move the hot air outside of the house. Intake vents are installed lower on the roof line than exhaust vents.
It’s important to bear in mind that since these vent types aim to achieve different tasks, combining an exhaust vent with an intake vent makes sense and improves your home’s ventilation.
With this in mind, let’s move on to explore the most common and popular types of roof vents in these two categories.
Top Exhaust-Style Vents
This is a common and popular type of vent that’s installed on the roof. How it works is that it gets placed at the roof’s peak and it moves across the entire roof line. By being placed at the peak of the roof, a ridge vent lets hot air escape from the attic.
This, combined with how it runs across the roof line, gives it a large surface area from which to eliminate hot air.
A ridge vent is small enough to allow for roofline installation.
It doesn’t require the addition of any stacks or hood in order for you to use it.
A ridge vent is ideal for sloped roofs, not flat roofs.
It relies on natural air circulation from wind blowing on your roof.
Box vents are installed in the form of one, two, or multiple units all across the roof so that ventilation can be enhanced. This vent, as its name suggests, is in a box shape. Since box vents don’t have to run all across the roof’s peak, they can easily be installed in smaller areas that require more ventilation.
This makes them useful and practical, especially if you have a roof with different, difficult-to-reach sections.
These are low-profile in design.
They have no moving parts, which makes them more durable.
You might have to install more than one box vent on your roof to get adequate ventilation.
Sometimes called whirlybirds, these turbines contain blades that are concealed inside a cover which rotates when moved by the wind. They then draw air up from inside your attic and push it out of the house. However, these turbines are not ideal for every location as they require a minimum wind speed of six miles per hour to spin.
A roof turbine relies on the wind and doesn’t have any motor.
Without requiring any electricity, roof turbines are an eco-friendly option.
They can be noisy because of their spinning parts.
This vent is similar in design to a ridge vent, but it’s ideal for a hip roof construction. Since this roof shape looks a bit like a pyramid with steep sides, it won’t offer ridges so that you can install a ridge vent.
A hip vet can therefore be installed instead. It will be placed over the side hip seams and it gets covered by the roof shingles. This is appealing to homeowners who don’t want the roof vent to be noticeable from the ground.
The hip vent is ideal for a roof that doesn’t have a ridge or not enough of one.
Hip vents are suitable for homes that have complex designs.
A hip vent will usually have to be installed with a soffit vent to increase its effectiveness and make it more cost-effective. (We’ll get to soffit vents later on in this article!)
Drip edge vent
A drip edge vent is ideal for a home that doesn’t have a roof overhang which is required for a soffit roof vent. This type of vent gets secured directly onto the edge of the roof, below the small overhang of the shingles. This produces a small gap that runs along the roof length. Just like with soffit vents, the drip edge vent will distribute air into the attic.
A drip edge vent is ideal for compact homes.
It is said to be good for a home in which a soffit vent is difficult or impossible to install.
It can be tricky to install.
This vent gives you more options because it runs on electricity, which is why it’s usually called an electricity-powered vent. It gets installed on the gable or roof and it’s got a low-profile design. It’s got an electric motor that pushes warm air outside of the attic, and this helps to reduce moisture from accumulating.
Since it’s low-profile, this vent can seamlessly feature in the home’s design.
A power vent can be noisy.
It has moving and electrical parts that can break down.
If you want to steer away from electricity and you live in a region that gets a lot of sunshine on a daily basis, you should consider a solar roof vent. The vent will have a solar panel attached to it so that it can run on the sun’s UV energy. You can find gable or roof solar vents. Basically, this vent moves air out of the attic so that it can be cooled down.
These solar vents are eco-friendly and save money on energy bills.
They’re easy to install.
While a solar vent can save you some money, its upfront cost might be more expensive than other vents.
It doesn’t move as much air as what you’ll achieve with an electricity-powered model.
Top Intake Roof Vents
This is the most popular type of intake vent for the roof. It gets installed on the eaves, which are found underneath the roof line.
You can find them in different variations but they usually have the same main design: they have small holes that draw cool air into the attic where it can force warm air out of it via an exhaust vent. This is why combining a soffit vent with a ridge vent is an effective way of improving your home and roof ventilation.
A soffit vent is easy to install, as long as you have enough space underneath the eaves or soffit.
They don’t get blocked easily, so they’re useful in regions experiencing lots of snowfall.
Soffit vents are built for air intake so they have to work with an exhaust vent to be most effective.
A gable vent uses cross-ventilation to move air through the attic. As its name suggests, a gable vent is ideal for a gable-style roof. This is because you can install a gable vent on both sides of the home.
It doesn’t work effectively on roof styles that are more complicated in design, otherwise their cross-ventilation can be blocked by peaks or other structures. Although you can find this type of vent in different shapes, a triangular gable vent is the most popular shape. It gets installed underneath the peak of the roof.
A gable vent that’s made out of metal can protect your roof against rodents.
This vent is cheaper than many other types of roof vents.
Gable vents are not compatible with all roof designs, such as hip roofs.
Although a cost-effective ventilation option, a gable vent isn’t the best at cooling down the attic.
A fascia vent, sometimes called an over-fascia vent, is designed for roofs that don’t have eaves which are of a suitable size to fit soffit vents. This vent gets placed at the top of a fascia board and gutter, so that it’s underneath the starting row of roof shingles. These vents encourage air intake when the wind hits the roof, instead of depending on hot air rising.
A fascia vent is ideal for a house where soffit vents can’t be installed.
It’s great for complex roofs where soffit vents on their own don’t offer enough ventilation.
Despite their advantages, a fascia vent is not as effective as a soffit vent. This is because its intake surface area is smaller.
Important Things To Know About Roof Vents And Ventilation
Now that you know a bit more about the types of roof vents that are available, there are some things to consider before you install them.
Keep an eye out for ventilation problems
How do you know if your home has inadequate ventilation? While looking for mold and mildew, or water damage, is a good move, this tip is also worth following during periods of snow in your area.
If it’s snowing and your roof is bare but the roofs of your neighbors are covered in snow, this can be a sign that your roof is warm, lacks ventilation, or doesn’t have the proper insulation installed.
Consider the building codes for ventilation
Building codes state that you should have one square foot of vent area for every 300 square feet of attic floor. This relies on the fact that half of your vent area is high on the roof, while the other half is low, placed in or within close proximity to the roof eaves. If that’s not the case, you should double the vent area that’s required – one per every 150 square feet – to ensure that you get enough.
Does ventilation make your roof shingles last longer?
Proper ventilation will have a positive effect on your shingles. This is because exposure to the heat can slowly cause them to deteriorate. Air ventilation keeps them cooler.
What is the stack effect in home ventilation?
Stack ventilation produces airflow via the natural force that’s created from changes in air temperature, pressure, and density levels between internal and external environments. The stack effect is when the air gets warmer, rises, and becomes less dense. This effect naturally provides ventilation.
Your home needs enough attic ventilation to protect it against issues such as mold and mildew, while also ensuring that your roof’s condition is maintained.
To ensure that you achieve this, you need to purchase the best roof vent for your home. In this article, we’ve featured all the types of exhaust and intake vents to know about, looking at their pros and cons, so you can make the best choice for your type of roof.
James Weldon is a professional roofing contractor with many years of experience on the job. He does not only handle large projects and provide excellent services for his company’s many clients; James Weldon also dedicates his spare time to teaching others useful tricks of the trade. Using BuildCampus as an avenue to reach many roofers and aspiring roofing contractors, James Weldon continues to provide high-quality educational posts and buying recommendations for anyone who visits the website.