Roof measured on a rafter
- Input
- 18,4°
- Expected output
- 33 %, ou 4:12
A common pitch for clay tile.
Carregando ferramenta… / Loading tool…
how to measure roof pitch
Every roofing material has a minimum pitch below which it leaks, and that figure is given as a percentage by some manufacturers and in X:12 format by others. Your phone measures the real angle of the roof and converts it to both forms at once.
A common pitch for clay tile.
Typical range for metal or fibre-cement sheet; check the manufacturer specification.
Percentage is the tangent of the angle times one hundred. It is not a proportion: 45 degrees is not 50 %, it is 100 %, because at that slope the rise equals the horizontal run. Near zero the relationship is nearly linear, so 1 degree is about 1.7 % and 5 degrees about 8.7 %, but it diverges quickly as the angle grows. The tool does this live so you never have to remember it.
It depends entirely on the covering. Clay, concrete, metal, fibre-cement and shingle roofs have very different minimums, and the correct figure is in the technical sheet for that specific product, not in a general rule. Measure the real pitch with the tool and compare it against that sheet.
No, and it is better not to. Roofs are slippery, often fragile surfaces, and falls from height are a leading cause of construction accidents. Measure from the eave, from framing visible inside, or by triangulation from the ground.
Tap to turn on the accelerometer. Everything is measured on your device and nothing is sent over the internet.
Zero degrees is the flat plane. This is how fall, ramps and roof pitch are measured.
Measurement happens entirely on your device, from the accelerometer. No angle, sensor reading or usage data leaves the browser.