How much does it cost to add a ridge vent, and what else comes with it?
Short answer. Adding a ridge vent to an existing roof means removing the ridge caps, cutting a slot, installing vent and new cap shingles, then usually closing off old box vents and checking soffit intake, so the price depends on ridge length, roof pitch and how much patching and intake work comes with it. If the roof is near replacement, adding the ridge vent during the new roof costs far less.
The core work
- Remove the existing ridge cap shingles.
- Snap lines and cut the slot to the vent's specified width, stopping short of the ends.
- Install the ridge vent with nails long enough to reach through the deck.
- Install new cap shingles over the vent.
What usually comes with it
- Closing old exhaust: box vents, turbines or a power fan on the same attic compete with the ridge vent. Each removed vent needs decking and shingle patches.
- Shingle matching: patches on a weathered roof may not match. On a 15 year old roof, the patches may show.
- Intake: a ridge vent without soffit intake does little. Adding vented soffit, cutting openings or adding baffles may be part of the job.
- Gable vents: often closed from inside so they do not short circuit the ridge.
What raises or lowers the price
- Longer ridges mean more vent and caps.
- Steep roofs need more safety setup.
- Older, brittle shingles at the ridge are harder to work around.
- A roof with short hip ridges may not have enough length to make it worthwhile.
Timing
If the roof has only a few years left, it usually makes sense to wait and do it with the replacement, when the deck is open and no patches are needed. See ridge vent vs box vents and signs you need a new roof.