How do you shingle a ridge cap?
Short answer. Finish the field shingles up to the peak on both sides, install any ridge vent, snap a line, then lay ridge cap pieces along the ridge starting at the end opposite the prevailing wind, each one overlapping the last at the manufacturer's exposure and nailed where the next piece will cover the nails. Face nail the final piece and seal its nail heads.
What a ridge cap shingle is
A ridge cap shingle is a piece made to bend over the peak or a hip, sealing the joint where two roof planes meet. On 3-tab roofs it can be cut from shingles; on architectural roofs it should be the manufacturer's matching cap product.
Step by step
- Field shingles: run each slope's top course over the peak or trim it so the two sides meet without gaps.
- Ventilation: if there is a ridge vent, cut the slot to the vent maker's dimensions and fasten the vent.
- Line: snap a chalk line on one side, measured from the peak, so the caps run straight.
- Hips first: start at the bottom of each hip and work upward, so the ridge caps will lap over the tops of the hips.
- Starting piece: trim the first cap at the end of the ridge so it sits flush with the rake.
- Lay the run: each cap overlaps the last at the exposure printed on the bundle, centered on the ridge.
- Nail: two nails per piece at the marked spots, long enough to reach through the vent and into the deck.
- Finish: cut the last piece to fit, face nail it, and cover the nail heads with sealant.
Tips
- Work from the end away from the prevailing wind so laps face downwind.
- Warm caps in cool weather so they bend without cracking.
- Do not stretch the exposure to make bundles go further.