Roofing
How Much Roofing Material Do I Need?
Measure the footprint of the building and choose the roof pitch. We apply the slope factor and return bundles.
- 01Measure
- 02Adjust
- 03Result
- 04Shop
01 — Measure
Tell us about the job
02 — Adjust
Material buffer
Hips, valleys and ridge caps eat material. Use 15% on complex roofs.
Before you start — measure this
- Building length
- Building width
- Roof pitch
- Overhang
03 — Result
99.1m²
Roofing area required
- Roofing squares
- 10.7
- Underlay
- 99.1 m²
04 — Shopping list
3 bundles ≈ 1 square (9.29 m²)
32 × 3.1 m²
- Total purchased
- 99.2 m²
- Expected leftover
- 0.1 m²
Optional — planning estimate, not a live price.
Stored in this browser only. No account needed.
How we got this number
- Footprint incl. overhang
- 80.6 m²
- Slope factor
- × 1.118
- Roof surface area
- 90.1 m²
- + 10% waste
- 99.1 m²
Planning estimate: this calculation helps you estimate material quantities. Actual requirements vary with site conditions, product coverage, installation method and waste. Confirm with the manufacturer or a qualified professional when appropriate.
What to know about this material
- A roofing square is 100 ft² (9.29 m²) — most shingle products are sold three bundles to the square.
- Add a ridge cap allowance separately; caps use about 1 bundle per 10 m of ridge.
- Roof work is high risk. Get a professional for steep or multi-storey roofs.
Frequently asked
- How do I work out roof area from the ground?
- Measure the building footprint, add the eaves overhang, then multiply by the slope factor for your pitch.
- What is a roofing square?
- 100 square feet, or 9.29 square metres. Shingles are usually three bundles per square.
- How much waste for shingles?
- 10% for a simple gable roof, 15% or more for hips, valleys and dormers.
Related calculators
What this calculator answers
The highest-intent, lowest-competition searches this page is built to answer outright — every one of them is a quantity question you can settle above without leaving the page.
- Roof pitch multiplierKD 6
- How many bundles of shingles do i needKD 13
Questions this page answers
This page is built around one job: convert roof footprint and pitch into squares, bundles and underlay.
- How many bundles of shingles per square?
- How to calculate roof area from ground measurements?
- Roof pitch multiplier table?
- How much underlayment for a roof?
Also known as: roof shingle calculator, how many bundles of shingles, roofing squares calculator, roof area estimator.