Ridge Cap Effective Cover calculator.
Count cap pieces across supplied ridge runs using the effective exposed length after specified overlap.
Your inputs
Use measurements from your plan and properties from your chosen product. Any prefilled values are illustrative.
A clear estimate starts here.
Enter your dimensions and product details to see the quantity and purchase breakdown.
Formula and assumptions
How this calculation works.
Supplied overlap is not a roof recommendation. Separate runs are rounded independently; intersections and special end pieces stay separate.
A worked example
Illustrative inputs only. Product properties and design dimensions are not recommendations for your project.
- Physical cap length
- 1 m
- Specified overlap
- 100 mm
- Measured ridge length
- 5 m
Ridge cap pieces: 6 pieces
Before you purchase
Use dimensions from your plan and properties from your chosen product. Any design spacing, section or fixing pattern must already be specified.
Supplied overlap is not a roof recommendation. Separate runs are rounded independently; intersections and special end pieces stay separate.
Method: dimensional arithmetic and user-supplied specifications. Software checks: 2026-10-04. Calculation and review policy.