Together soffits and fascias form a protective but breathable barrier around the edge of your roof. When combined with ridge line and other roof vents, they provide attic ventilation. The following is a description of soffits, fascias and the various roof vents, along with an explanation of how the most efficient combination provides attic ventilation.
All About Soffits
Soffits are the exposed areas underneath the overhanging roof eaves. Most modern soffits are made from wood, vinyl or aluminum, all of which withstand exposure to heat and moisture. Soffits are located near the gutters and are sometime exposed to runoff from blocked drains, as well as wet weather conditions. They also, along with fascias, help keep bats, birds and other wildlife out of your attic.
In addition to giving a finished look to the underside of your roof, soffits play a part in ventilating the attic. They have small vents that pull air into the attic space. Attics without adequate ventilation can develop rot in the rafters and sheathing. Hot attics can also cause air conditioning units to work harder than they need to, increasing energy bills.
All About Fascias
Fascias are the vertical finishing edges along the edges of the roof. They are connected at the end of the rafters where the gutters are attached. The fascia acts as a protective barrier between the end of the roof and the elements.
This feature also makes the roof look more finished because it covers up any uneven spots along the roof edge. Fascias are made of the same materials as soffits, but they have no vent holes along the sides. A slight gap is usually left at the top of the fascia where it meets the roof line to provide ventilation.
Roof vents come in four non-powered varieties.
Ridge vents are located on the ridge line, or roof peak. They run from one edge of the roof to the other, with the ends pointing slightly downward to discourage water and snow from getting inside. The vents are laid end to end along the roof line and nailed down. Then, roofing shingles are fitted over the vents to give the roof a more finished look.
Static vents are simply protected holes in the roof that allow air from the attic to escape. Some, like the eyebrow vents, are barely visible from ground level, while others have round or square covers that are horizontal to the roof surface.
A gable is the peaked point created when two sides of a roof meet at the roof peak. Gable vents are installed at the top of these triangles, along the gable walls. The higher up the gable vent, the more hot air will be forced outside. Sometimes the vents are combined with gable fans, mounted just behind the louvers.
These are mushroom-shaped vents that are most often found on flat roofs. They are designed to catch the wind, which causes an internal fan to spin and force hot air out of the attic.
Putting Soffits, Fascias and Ridge Vents Together
Combining the soffit and fascias with the ridge line vent creates the most efficient attic ventilation system. Cool air enters from the bottom of the soffit, with a little more coming in from the gap on top of the fascia. As it enters the attic, it forces the warmer air up towards the top of the roof. The air enters the ridge vent and is forced out. This ventilation system requires no electricity or other power source. The exchange of air may slow down during the cooler seasons, but as long as the vents are kept clear, the process will go on indefinitely.Share