What Is a Gable Vent?
There are several types of roof or attic vents for houses available, so it’s helpful to know what gable vents are and how they compare with other types of roof vents for houses and other structures.
Gable Vents
You’ll see gable vents on some homes with peaked roofs. The section of the home exterior that encloses the space created by the angled roof — typically the attic — is the gable. As the name implies, gables for houses often have gable vents on each end of the roof to allow air circulation as cool air enters and hot air exits the attic. A set of louvers form the attic vent cover. These vent louvres create a more decorative look. Louver vents also help keep rain and snow from entering the attic. In some houses you may see gable vents with fans mounted on the attic side of the house to create improved air circulation.
A gable vent fan is a type of attic van that mounts to a vent on the gable wall. Take a look at our comparison of whole-house fans and attic fans to learn which type is right for your home.
Gable Vents and Soffit Vents
Gable vents often work with soffit vents, another type of roof vent. Soffit vents are perforated panels on the underside of the eaves of a house roof. This placement on the roof overhang allows the airflow to pull cool air up through the soffit vents where it can pass through the attic and exit through the gable vents.
Gable Vents vs. Ridge Vents
A ridge vent is a type of roof vent that runs along the length of the roof ridge. Roofers might install a ridge vent either during the construction of a new home or as part of a roof replacement. If a home has a ridge vent it will probably not have gable vents. Ridge vents can provide more ventilation but they’re typically a more expensive option than gable vents. Gable vents offer the additional benefit of being easier to install.
Deciding on Vent Types
Some homes and climates may be better suited to ridge vents, gable vents or other types of vents and building codes may have specific ventilation requirements. If you’re deciding between a ridge vent and gable vents or considering power roof vents, turbine vents or static roof louvers, talk to a ventilation professional to get a recommendation specific to your house.
The Importance of Venting a Roof
Gable vents and other types of roof vents for houses allow moisture and warm or hot air to escape the attic space of the structure while allowing cooler air from outside to enter the space. This air circulation has several benefits that make these vent systems key components on a house.
- In the summer, the temperature and moisture levels in the attic space can become high enough to damage your roof and require repairs or reduce the lifespan of shingles and other roofing materials. Vents release the heat and moisture.
- Ventilation that allows excess moisture to escape also reduces the risk of mold and mildew growth in the attic.
- Heat in the attic transfers to the rooms below, making your living spaces less comfortable and requiring your cooling system to work harder. Vents can bring cooler air into the attic.
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In the winter, good roof ventilation can reduce the risk of ice dams. Ice dams form when ice or snow on a roof melts due to warm air in an attic, flows down the roof and refreezes at the unheated eaves. An ice dam prevents proper drainage from the roof, allowing water to back up under the roofing materials and cause damage.
Gable Vent Sizing
Gable vents are available in many shapes and sizes. In addition to triangles, gable vents are available in shapes such as circles, octagons, squares, rectangles, ovals and more, so you can choose a shape that looks best with your home. Of course, if you have a gable vent fan, you’ll need to choose a vent that fits the fan.
The size and number of vents on a home determine how much air circulation is possible. Larger attic spaces will require more vent area to create the right amount of circulation. To understand how many gable vents you need and what size they need to be, it’s best to consult a professional, but there are a couple of tips that can help you plan.
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If you’re replacing gable vents, you may be able to simply replace them with vents of the same shape and size.
- If you need gable end vents for a new home or an addition, you can estimate the amount of vent space you need based on the size of your attic if you know the code requirements for your area. In some cases, you can expect to need at least one foot of vent area for every 300 square feet of attic floor space. But for some houses you may need as much as a foot of vent space for every 150 square feet of attic space.
Keep in mind, these tips only give you broad estimates to use as a starting point. Your local building codes, the size and shape of your home, the design of your roof and other factors determine the number of vents you need. Talk to a professional for estimates specific to your home.
Gable Vent Tips
Often there’s not a lot of maintenance required for attic gable vents. However, there are some things that can reduce their effectiveness.
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Obstructed vents won’t allow good airflow. Gable vent screens keep debris, animals and insects out of the attic space. If a screen is blocked with dust, cobwebs, etc. it’ll need to be cleared.
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If a vent screen is cut or damaged it’ll need repair or you’ll need a replacement screen. A damaged screen allows insects and animal pests into your attic. From there they’ll have access to the house structure and your living spaces.
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The louvers on the attic vent covers may create an inviting location for a bee or wasp nest. One of these will block some of the airflow through the vented louvers, making the vent less efficient. Having the nest removed can restore good airflow.
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Gaps between the attic and the rooms below it can allow the vents to draw cooled or heated air from the living space. In addition to a loss of heating and cooling efficiency, the conditioned air in the attic can create problems with moisture and ice dams. Seal up any gaps you find.
Choosing Gable Vents for Your Home
Attic gable vents can be an effective means of improving air circulation underneath your roof. Better circulation reduces the risk of damage that excess heat and moisture can cause. When making changes to your roof ventilation system or when planning ventilation for a new home or an addition to your existing home, you should always talk to a ventilation professional to get recommendations.
From there, a Lowe’s associate can help you find the right gable vents. Lowe’s offers vents in a range of shapes, sizes and colors with materials such as wood, vinyl, PVC (polyvinyl chloride), steel, aluminum and more. And you can look for decorative gable vents that create good attic ventilation while improving the look of your home exterior.