Roof Ventilation Explained: Why It Matters for Shingle Life
How proper ridge and soffit venting can double shingle longevity in hot climates.
Inadequate attic ventilation can cut asphalt shingle life by 30-50%. Heat trapped under the roof cooks shingles from below — and most homes built before 2000 have ventilation systems that fall short of modern code minimums.
The intake/exhaust balance
Modern code requires 1 sq ft of vent area per 150 sq ft of attic, split roughly 50/50 between intake (soffit) and exhaust (ridge or gable).
Common problems: blocked soffit vents (insulation pushed against the eave), insufficient ridge venting, and homes with only gable vents that create dead-air pockets.
When to upgrade ventilation
During any roof replacement — adding continuous ridge vent and unblocking soffit vents costs $300-$1,200 extra and dramatically extends shingle life.
Outside of a re-roof, retrofitting ventilation runs $800-$2,500 depending on the configuration. Pays back through extended roof life and lower summer cooling bills.