Do I need ridge cap shingles, and how many?
Short answer. Yes. Laminated architectural shingles crack if folded over a ridge, so hips and ridges need dedicated hip and ridge cap shingles, and manufacturers generally require their own cap product for full system warranties. To figure how many, measure the total linear feet of hips and ridges, divide by the coverage printed on the cap bundle, and add a little extra.
Why you cannot cut your own
On old 3-tab roofs, installers cut caps from regular shingles and bent them over the ridge. Architectural shingles are two bonded layers and too stiff to fold, so they crack along the bend and leave the ridge exposed. Dedicated cap shingles are pre-scored or pre-bent, thicker for wind resistance, and color matched to each shingle line.
How many you need
- Add up the linear feet of every ridge and every hip. A measurement report or estimate usually lists both.
- Check the cap product's coverage per bundle on the wrapper; products commonly cover somewhere around 20 to 35 linear feet per bundle.
- Divide, round up, and add a bundle for waste and future repairs.
Example: 60 feet of ridge plus 80 feet of hips is 140 linear feet. At 25 feet per bundle that is 5.6, so order 6 bundles plus one spare.
Ridge vents
If the roof has a ridge vent, the caps go right over it, so the count does not change, but the nails need to be longer. Our page on ridge vents vs box vents explains the vent itself.
Where caps are not used
- Valleys: covered by woven or cut shingles over leak barrier, not caps.
- Rakes and eaves: finished with starter strip and drip edge.
- Roof-to-wall joints: handled with flashing.
For measuring the rest of the roof, see how roofers measure a roof.