Roof Shingle Bundles & Waste Calculator
Calculate roofing squares, bundles, accessories, and dumpster weight
Roof shingle calculator — quick guide & how it works
How to use it
Enter each rectangular roof section as plan length × width. Set a global pitch (slope multiplier) and a waste/complexity percent. Choose bundles per square (3 or 4) and add linear footage for starter and ridge/hip as needed.
What you’ll get
The tool returns field bundles, starter bundles, ridge/hip bundles, and total bundles, plus a dumpster weight estimate when tearing off old shingles. Counts are rounded up for ordering.
Tips for accurate inputs
- Split L-shapes into rectangles and enter both; the calculator sums them.
- Use the lower end of waste for simple gables, higher for hips/valleys and lots of facets.
- Starter bundles cover ~100 ft (30 m); ridge/hip ~33 ft (10 m)—check your product specs.
Assumptions in the math
Plan area is multiplied by the pitch factor √(rise²+run²)/run and then by (1+waste). Squares = surface/100. Field bundles = ceil(squares × density). Accessories are computed from linear coverage, and dumpster weight is squares × lb/sq × layers.
How the shingle & dumpster estimates work
- Plan area = Σ(length × width). Metric inputs convert to feet internally.
- Pitch multiplier as above (e.g., 6/12 ≈ 1.12; 12/12 ≈ 1.41).
- Surface = plan × multiplier; with waste = surface × (1 + waste%).
- Squares = surface/100; field bundles = ceil(squares × 3 or 4).
- Starters ≈ 100 ft/bundle (30 m); ridge/hip ≈ 33 ft/bundle (10 m).
- Dumpster weight = squares(with waste) × lb/sq × layers (asphalt shingles only).
Roof shingle calculator FAQs
What’s a “square”?
100 ft² (≈9.29 m²) of roof surface. Bundles are derived from squares and your density choice.
Do starter and ridge/hip match field coverage?
No—those are sold by linear coverage, so the calculator asks for linear feet/meters and computes accessory bundles separately.
How much waste should I choose?
7–12% for simple gables; 12–15%+ for hips/valleys, dormers, and complex layouts. Round up if unsure.
Does the dumpster estimate include underlayment or wood?
No—rule of thumb for asphalt shingles only. Moisture, nails, and mixed debris add weight; check with your hauler.
Can I use metric?
Yes—switch to Metric to enter meters; helper text and unit chips update to avoid confusion.