What types of vents are on a roof?
Short answer. Roof vents fall into two groups: attic ventilation vents, such as ridge vents, box vents, turbines, off-ridge vents, powered and solar fans and intake vents at the soffits or roof edge, and plumbing or appliance vents, such as plumbing stacks, bath and kitchen exhaust caps and furnace or water heater flues. Each needs its own type of flashing and upkeep.
Attic exhaust vents
- Ridge vent: continuous along the peak, under the cap shingles.
- Box vent: also called static, louver or turtle vent; a square hood near the ridge.
- Off-ridge vent: a short, low rectangle just below the peak.
- Turbine: a round head that spins in the wind.
- Powered attic ventilator: a dome over an electric fan with a thermostat.
- Solar attic fan: a similar dome with a built-in panel.
- Gable vent: in the wall at each end of the attic rather than on the roof surface.
- Cupola: a decorative structure on the ridge that may or may not vent.
Attic intake vents
- Soffit vents: under the eaves.
- Edge intake vents: on the roof at the eave, for homes without soffits.
Non-attic vents
- Plumbing stack: an open PVC or cast iron pipe with a boot.
- Bath and kitchen exhaust caps: low hooded caps with dampers.
- Gas appliance flues: metal pipe with a cap and storm collar, or plastic pipe for high efficiency units.
Rules of thumb
Use only one type of attic exhaust per attic space. Leave changes to appliance flues to the right trade. Every penetration needs flashing that sheds water. See ridge vent vs box vents and roof flashing explained.