Are ridge vents good or bad for a house?
Short answer. Ridge vents are good for most houses with a gable roof and vented soffits, and bad only when the setup around them is wrong. Whether yours is good or bad depends on the intake, how the slot was cut and the vent installed, and whether other exhaust vents compete with it.
Your ridge vent is probably doing its job if
- The soffits have vents along most of the eaves, and from inside the attic you can see daylight or feel airflow at the eave edge.
- Insulation stops short of the soffit openings, ideally behind cardboard or foam baffles.
- There are no gable vents, box vents, or power fans on the same attic, or they have been closed off.
- The vent has an external baffle or weather filter, and the cap shingles are flat and fully nailed.
- The underside of the decking near the peak is dry and the nail tips are not rusty.
Warning signs it is working against you
- Water spots or drips on the attic floor directly under the ridge after windy storms.
- Cap shingles lifting, cracked, or missing along the peak.
- Dark staining, mildew, or condensation on the decking, which points to poor airflow.
- An attic that stays hot late into the evening, and upstairs rooms that are hard to cool.
Pros and cons at a glance
Pros: even airflow across the whole ridge, no moving parts, no electricity, a low profile, and fewer roof penetrations. Cons: it depends entirely on soffit intake, it is limited on short hip ridges, cheap versions can admit wind driven rain, and the slot has to be cut correctly.
Most problems are fixable without abandoning the ridge vent: adding intake, sealing off competing exhaust, or swapping a low quality vent for a baffled one during a reroof. More detail is in roof ventilation basics and what to expect from a roof inspection.