Can you install ridge vent on hips?
Why hips are different from ridges
- Slope: a ridge is level, so water sheds off both sides. A hip slopes down, so rain runs along it, testing any opening in a way a ridge never does.
- Framing: the hip rafter and the short jack rafters framing into it leave less clear deck to cut a slot along.
- Wind exposure: hip caps take wind from several directions as it wraps the corner.
The exhaust height problem
The residential code's balanced venting option counts upper vents only if they are within 3 feet of the ridge, measured vertically. A slot running the full length of a hip reaches down near the eaves, where it behaves like intake. That can short circuit the soffits, pulling air in low on the hip and out at the ridge without ever sweeping the lower deck. If a hip vent is used, the slot is usually kept to the upper portion near the ridge.
When hip venting makes sense
Hip roofs often have short main ridges that cannot provide enough exhaust by themselves. A vent product made or approved for hips, installed to its own instructions, can add exhaust length without adding box vents. Otherwise, box vents placed high on the slopes are the usual answer, sized so total exhaust does not exceed intake.
What not to do
Do not cut slots under ordinary ridge vent on hips unless the manufacturer approves it, and do not mix hip vents and box vents on the same attic without a calculation. Read ridge vent vs box vents and roof ventilation basics.