Roof Ridge Cap Calculator
Estimate roof ridge-cap pieces, bundle quantity and material cost from ridge length, hip length, exposure and package count.
Default project preview
7 bundles
Total cap run
78 ft
Base cap pieces
167
Order pieces
184
Purchased pieces
210
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Total ridge length
Enter this project assumption in ft. The current imperial default is 42 ft.
Total hip length
Enter this project assumption in ft. The current imperial default is 36 ft.
Installed exposure per cap
Enter this project assumption in in. The current imperial default is 5.625 in.
Waste allowance
Enter this project assumption in %. The current imperial default is 10 %. Minimum: 0. Maximum: 50.
Cap pieces per bundle
Enter this project assumption in pieces. The current imperial default is 30 pieces. Minimum: 1.
Price per bundle
Enter this project assumption in per bundle. The current imperial default is 62 per bundle. Minimum: 0.
How to read the outputs
Total cap run
ridge plus hips. Default preview: 78 ft.
Base cap pieces
before waste. Default preview: 167.
Order pieces
10% allowance. Default preview: 184.
Purchased pieces
rounded bundles. Default preview: 210.
Material allowance
bundles × entered price. Default preview: $434.00.
Installed exposure
editable product assumption. Default preview: 5.625 in.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Total cap run = ridge length + hip length. Base pieces = total run ÷ installed exposure. Waste is added, then bundles are rounded up from pieces per bundle.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: July 30, 2026
Estimate ridge and hip cap pieces or bundles from total cap length, product exposure and waste.
Calculation steps
- 1Add all ridge and hip runs.
- 2Convert product exposure to linear coverage per piece.
- 3Add starter, end and waste pieces.
- 4Round upward to full bundles.
Worked numerical example
A roof with 54 ft of ridge and 36 ft of hips has 90 ft of cap run. At 10 in exposure, 108 pieces are needed; with 8% allowance, round to 117 pieces or the next full bundle.
Purchasing and rounding
Use the cap product approved for the field shingles and account for bundle coverage rather than shingle count alone.
Interpret the result
The result is an order quantity; ventilation opening, fastening and weather exposure require separate verification.
Page-specific assumptions
- One cap product.
- Uniform exposure.
- Measured runs include all hips and ridges.
Common mistakes
- Using field shingles without checking approval.
- Confusing nominal piece length with exposure.
- Forgetting hip waste.
Primary and technical references
BuildMeter provides planning estimates, not engineering, architectural, electrical, mechanical, plumbing, permit or code approval. Review the methodology and verify final decisions with product documentation and qualified professionals.
FAQ
Roof Ridge Cap Calculator questions
Are ridge caps counted by full shingle length?+
No. Use the installed exposure—the portion of each cap left visible after overlap.
Should hip lines be included?+
Yes, when the roof uses the same cap product on hips. Enter the combined hip length separately.
Does this include ridge ventilation?+
It estimates cap material only. Ridge vent length, end plugs and fasteners should be planned separately.