Roof Soffit Venting 101: Everything You Need to Know

An image of roof soffit venting.

Between picking the best type of roof soffit venting and determining how big the vent should be, this is your guide to roof soffit venting.

3 min read

What Are Soffit Vents?

Do you know the underside on the eaves of your roof? The part that hangs down over the side of your house? That's what a soffit is.

The purpose of putting vents here is to allow air to flow from the outside of your home into your attic.

It's important to provide your attic with some cool air circulating through it to prevent mold and mildew from growing. Heat causes moisture, which can lead to these issues and a range of health problems.

Roof Soffit Venting Types

There are three common styles of soffit vents.

Lanced vents have tiny slats all along their surface. These slats are little rectangular holes no bigger than your fingernail. They're designed to let air into your attic without bringing in too much wind or sucking dust upwards into your home.

Round soffit vents- those with round holes rather than rectangular ones- are intended to do the same thing

If you don't like looking at the holes, that's also alright. There are hidden vents, too, that bring air up through large slits that make your vent look paneled. While aesthetically pleasing, however, these vents are harder to clean and potentially less effective.

You also will have many options as to what material you want to build your roof soffit vent from. Wood is an option, but it traps moisture and is susceptible to damage from termites and other pests. For this reason, aluminum, vinyl, or man-made composite is a better alternative.

Soffit Sizing Tips

If you're still in the process of renovating your home and building your soffits, you'll need to figure out the specific size that you need your soffit to be. This means that it's important to calculate the soffit requirements for your home.

Once that's done, you'll need to calculate the necessary vent area on your individual soffit. Multiply your attic length with its width in feet. This will tell you the overall area of your attic. After that, divide your area by 150. The result is the total square feet of vent space needed.

Installing Your Soffit Vents

Now that you know exactly what soffit vents you want, it's time to order and install them! While many companies will send people out to help with installation, it's also possible (and easy!) to DIY.

Hop on a ladder and mark the places on your eaves that you want your soffit vents to be. Make sure that they're evenly spaced and fit between the rafters of your roof.

After that, you can use a circular saw or a saber saw to cut a hole that's slightly smaller than the vent in your eaves. Make sure that the hole isn't obstructed by insulation or anything else before securing your vent into place!

Get Started

Now that you know the basics on roof soffit venting, it's time to make sure that your home has the appropriate siding and soffits so that you can install your vents easily. Learn more about measuring your home for renovations!

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