Roof Shingles: Counting Bundles Over Hips and Valleys
Roof cuts at hips and valleys waste shingles, and a plain area division misses them. This post shows the allowance that covers the cutting.
What is the Roof Shingles Calculator?
Enter the roof area including slope, and the coverage of one bundle, and the tool adds a 10 percent allowance for cuts at hips, valleys, and edges before rounding up. The allowance is shown separately.
How to use it
- Measure the roof area including its slope, not just the footprint.
- Enter the coverage of one bundle.
- Click Count Bundles.
Worked example
100 sq m at 3 sq m per bundle needs 33.33 bundles exactly, or 36.67 with waste, rounded up to 37 bundles.
Is roof area the same as house footprint?
No. Slope increases the true roof area above the footprint, so measure the slopes themselves.
Frequently asked questions
Do ridge caps need extra bundles?
Ridge caps are often counted separately, so check whether your bundle figure already includes them.
Should complex roofs allow more?
Yes, roofs with many valleys or dormers may need a 15 percent allowance.