Metal Roofing Estimator
Calculate total square footage, material squares, and estimated costs for your metal roof project.
Estimation Results
How to Calculate Metal Roofing Needs
Planning a metal roofing project requires more than just basic area measurements. Unlike flat surfaces, roofs have a pitch (slope) that increases the actual surface area compared to the home's footprint. Our calculator uses the standard pitch multiplier method to ensure you order enough panels and trim.
Understanding "Squares" in Roofing
Professional roofers use the term "Square" as a unit of measurement. One square equals exactly 100 square feet of roofing surface. For example, if your roof surface area is 2,400 square feet, you will need 24 squares of metal material.
The Impact of Roof Pitch
The pitch is the vertical rise of the roof over a 12-inch horizontal run. A 6/12 pitch means the roof rises 6 inches for every 12 inches it runs horizontally. This angle increases the total area you must cover. Below is a quick reference table for common pitch multipliers:
| Roof Pitch | Multiplier (Factor) | Angle (Degrees) |
|---|---|---|
| 3/12 | 1.03 | 14.0° |
| 6/12 | 1.12 | 26.6° |
| 9/12 | 1.25 | 36.9° |
| 12/12 | 1.42 | 45.0° |
Waste and Overlap
When calculating metal roofing, it is standard practice to add a waste factor. For a simple gable roof, 10% is usually sufficient. However, if your roof has many valleys, hips, or dormers, you should increase this to 15% or 20% to account for complex cuts and overlapping panels.
Example Calculation
If you have a footprint of 1,000 sq ft and a standard 6/12 pitch:
- Surface Area: 1,000 x 1.12 = 1,120 sq ft
- With 10% Waste: 1,120 x 1.10 = 1,232 sq ft
- Total Squares: 12.32 squares