Soffit and Attic Vent Maintenance

How attic ventilation works

ARMA's ventilation best-practice guidance describes a balanced system: outside air enters through intake vents at the eaves and leaves through exhaust vents high on the roof. The flow carries away summer heat and winter moisture from the attic. Shingle manufacturers commonly require adequate ventilation as a warranty condition, so it is worth getting right.

Types of vents you'll see on valley homes

• Soffit vents: perforated panels, strip vents or individual round or rectangular vents under the eave. These are intake.
• Ridge vents: a continuous vent along the peak, covered by cap shingles. Exhaust.
• Gable vents: louvered openings high in the end walls.
• Box or turbine vents: individual vents near the ridge.

Mixing exhaust types (for example a ridge vent plus box vents) can short-circuit airflow so air is pulled from one exhaust into another instead of from the soffits. Ask a roofer before adding vents.

Maintenance checklist

• From the attic, confirm insulation isn't packed against soffit intakes. Baffles keep a channel open.
• From outside, look for paint-clogged perforations, dust or wasp nests in soffit vents.
• Check vent screens for tears or gnawing, a common rodent entry (see entry points).
• Look for daylight around gable vent frames and ridge vent ends.
• In winter, check the underside of the roof deck for dampness or frost-like staining.
• After soffit or fascia repairs, confirm vents were reinstalled, not covered (fascia repair).

Ventilation and energy

Ventilation removes heat from the attic but does not replace insulation and air sealing between the living space and the attic. ENERGY STAR's seal-and-insulate guidance covers that side, and California's Title 24 standards set requirements for new work. For summer comfort in the valley, sealing attic air leaks and adding insulation often matters as much as the vents.