We’ve talked a lot about ventilation and how important it is to the health of your roof. It’s something that can’t be emphasized enough—poor/no ventilation can result in damage to your roof and the interior of your home—in addition to excessive heating and cooling bills.

While we’ve examined some of the components and options for a ventilation system, we thought we’d take some time to go through some of the most common.

The Basics:
Good ventilation allows warm air to escape from underneath the roof, and cooler air from the underside of the roof to replace it. This keeps heat from accumulating on your roof’s surface, which prevents ice dams, interior condensation, high heating & cooling bills, buckling roof shingles, peeling paint, and many more problems.

Most residential ventilation is a “passive” ventilation, meaning that it uses natural forces to circulate the air—no fans, or motors are needed.

Types of Vents:

Soffit Vent: Allows air to ENTER the ventilation system. 

A soffit is the underside of your roof’s overhang. This is most often covered by vinyl (but can also be made out of steel, aluminum, wood, etc). Soffit vents are simply vents in the soffit that allow for fresh, cooler air to enter the ventilation system. There are many different types of soffit vent depending on your budget and aesthetic. Some of the most common types:

  1. Hidden Soffit Vents: draws in the ventilation you need, with a “clean” design—the vents are virtually hidden.
  2. Undereave Vent: these come in 16”x4” or 16”x8” sizes, and can be placed directly into a wood soffit.
  3. Perforated Soffit Vents: the perforations can be in each soffit panel, or in sections.

Edge Vent: Allows air to ENTER the ventilation system.

Some homes do not have a soffit—they have little or no overhang. This is great in terms of allowing light into your windows, but it does not allow for the installation of soffit vents. Edge vents are often the answer. A channel is cut into your roof deck about a half foot away from the edge. An edge vent is attached, and then covered with shingles. This allows air to enter under the shingles and into the channel and the ventilation system. Edge vents can be just as effective as soffit vents.

Box Vent: Allows air to EXIT the ventilation system.

These vents are installed over holes cut into the roof. There are often several. Box vents allow for the release of warmer air, but warm air can accumulate in the spaces between the rafters of your attic between where the vents are located.

Ridge Vent: Allows air to EXIT the ventilation system

A ridge vent is installed along the peak of your roof. It works like a vacuum, allowing continuous air flow thought every rafter, and warm air and moisture to exit the roofing system.

Gable Vent: Depending on location, allows air to ENTER and/or EXIT the ventilation system.

Gable vents are seen mostly on older homes, and are decorative. They occur where two slopes of a roof meet. Most are made of wood, with a screen wire backing to keep out animals and insects. Some older homes have a gable vent in the front, and one in the back, which acts as the entire ventilation system. Gables work best, however, when they are in tandem with soffit or edge vents.

Similar to box vents, pockets of warm air can get trapped in the system AND these vents rely on wind to circulate air. If there is no wind, or the wind is in the wrong direction, it can severely impact how effective these can be. Gable vents are not recommended for homes. If you have a gable vent, it can simply be covered from the inside (leaving its decorative appeal) and a ridge vent can be installed in its place.

Each roof is different, as is each roof’s ventilation needs. Allstate Roofing & More, LLC’s team will be able to work with you to assess your roof, and what system will ensure a great result for you! Evaluations and estimates are always free to residential customers. Contact us anytime at 585-400-7663 or office@400roof.com.