How this calculator works
Hip and ridge shingles finish the peaks of a roof. They are sold in small bundles that cover a stated number of linear feet, so the count is a division: the length of the ridges and hips, plus a margin for cuts, divided by the feet one bundle covers, rounded up.
Worked example: a roof with 40 ft of ridge needs 2 bundles at 25 linear ft each, with 5% extra, or 2 at 33 linear ft. Add 60 ft of hips and the ridge cap is 5 bundles at 25 ft.
Assumptions and sources
- Assumptions used: 5% waste added; 25 linear ft per bundle, as you entered.
- The coverage per bundle depends on the product and on the exposure, so use the figure on the wrapper. Ridge cap shingles are often cut from the same bundles as the starter and hip pieces, so the roofing calculator's bundle count may already include some: ask the supplier. Ridge vent needs a cap that is rated for it, and the cap covers the vent as well as the ridge.
The formula and a worked example are shown above, so you can check any result by hand. Read how we calculate and check our numbers. Results are estimates for planning: supplier products vary, so check the size printed on the label.
Bundles of ridge cap by ridge length
With 5% extra. Add the hips to the ridge length.
| Ridge and hips | 25 ft bundles | 33 ft bundles |
|---|---|---|
| 20 ft | 1 | 1 |
| 30 ft | 2 | 1 |
| 40 ft | 2 | 2 |
| 60 ft | 3 | 2 |
| 80 ft | 4 | 3 |
| 100 ft | 5 | 4 |
| 150 ft | 7 | 5 |
Tips before you buy
- Check the number on the wrapper. Bundles from different makers cover different lengths, and a "bundle" of ridge cap is much smaller than a bundle of ordinary shingles.
- Measure hips along the hip, which is longer than the horizontal run. A hip on a 6/12 roof is about 6% longer than its own horizontal run (more on a steeper pitch).
- Buy ridge cap in the same color and from the same batch as the shingles, and order it with them.
- On a ridge vent, use a cap that the vent maker says suits it, and nail it with longer nails that reach the deck.
- Keep a spare bundle for repairs: ridge cap is the part of the roof that sees the most sun and wears first.
Tools & materials for this project
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Frequently asked questions
How many bundles of ridge cap do I need?
Divide the total length of the ridges and hips (plus 5% for cuts) by the feet a bundle covers. 40 ft of ridge takes 2 bundles at 25 linear ft per bundle.
How many linear feet does a bundle of ridge cap cover?
It depends on the product: 25 linear ft is common, and some products cover 33. Read the wrapper.
Do I measure the hips differently from the ridge?
Measure each hip along its slope: it is longer than its horizontal run. Add the hips to the ridge length, then enter the total.
Can I make ridge cap from ordinary shingles?
You can cut three-tab shingles into caps, but purpose-made hip and ridge shingles are thicker and are made to bend over the peak without cracking. Follow the shingle maker's instructions.
How much extra should I buy?
About 5% for a simple roof, and 10% where there are many hips, valleys and ends.
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Related calculators & guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.