What is an air vent on a roof, and what do air vents in a roof do?
The air vents you will see on most Georgia roofs
- Ridge vent: a low, continuous vent along the peak, usually covered with cap shingles so it barely shows.
- Box vents (also called static or turtle vents): square or rounded hoods set a few feet below the ridge, usually in a row.
- Turbine vents: spinning domes that turn with wind and rising heat.
- Power vents: larger domes with an electric or solar fan inside.
- Gable vents: louvered openings in the triangular end walls rather than on the roof surface.
The intake half of the system is usually not on the roof at all. It is the perforated or slotted soffit under the eaves. Without intake, even a good exhaust vent moves very little air.
What is not an air vent
Round pipes with rubber or lead collars are plumbing vents for the drains. Metal pipes with a cap are usually flues for a gas furnace or water heater. Small hooded caps may be bath fan or kitchen exhausts. These are separate systems and should never be tied into the attic vents.
Why air vents matter here
Summer attics in Georgia get extremely hot, and humid air carries moisture into the attic all year. Moving that air out helps keep the roof deck dry, reduces heat stress on shingles, and keeps the setup in line with what shingle manufacturers require for their warranties. Building codes also set a minimum amount of vent opening based on attic size. For how intake and exhaust work together, see roof ventilation basics and ridge vent vs box vents.
If a vent hood is cracked, loose, or rusted, it is a leak point. Hail often cracks plastic vent hoods before it visibly damages shingles, so vents are one of the first things worth checking after a storm.