How do you ridge vent a shingle roof the right way?
Short answer. To ridge vent a shingle roof properly, treat it as a system: confirm or add soffit or edge intake, calculate how many feet of vent the attic needs, cut the slot to the vent's specifications, close all other exhaust, and cover the vent with matching hip and ridge cap shingles. On hip roofs with short ridges, add hip vents or choose a different exhaust plan.
Design before you cut
- Intake: soffit vents along most of the eaves, with baffles so insulation does not block them. Without soffits, add intake vents at the roof edge under the shingles.
- Required length: attic area divided by 600, times 144, divided by the vent's rating per foot gives the feet of open slot for a balanced 1/300 system.
- Available length: measure the ridge, subtract the end stops (commonly at least 6 inches at each end), and compare.
- Other exhaust: box vents, turbines, fans, and gable vents should be removed or closed.
Roof shape matters
- Gable roofs: ideal for ridge venting, with long continuous ridges.
- Hip roofs: short ridges may not provide enough length. Hip vents installed along the hips, or box vents high on the slopes, can supplement or replace the ridge vent.
- Complex roofs: separate ridges over different attic sections each need their own exhaust and intake.
- Low slope sections: ridge vents are designed for a minimum slope, so check the product's limits.
Matching the shingles
Use a shingle-over vent with an external baffle, and cap it with hip and ridge shingles matched to your field shingles. Many shingle manufacturers sell their own vents and caps as part of a system, which can matter for enhanced warranties.
Best timing
The ideal time to ridge vent a shingle roof is during a replacement, when the ridge, old vents, and edge details are already being redone. Retrofitting an existing roof works, but patches where old vents are removed may not blend with weathered shingles. See ridge vent vs box vents and what to expect on roof replacement day.