Roof Pitch Gauge +

Roof Pitch Gauge reads the slope of a roof from your phone's motion sensor. Lay the phone on the roof deck or a rafter, hold still, and the reading locks by itself — lift the phone and the number stays on screen. ▶ OPEN AND READ The gauge is the first screen: one big number in the notation used where you work, with the other three underneath. • x/12 rise over run, shown to the nearest ½ (≈ marks a rounded value) • degrees • percent grade • rise per 10 (寸 / 치) Tap the number to switch. A stability ring fills while the phone is still and turns green when the reading locks. It only shows that the phone has stopped moving; it does not rate the reading. ▶ CALIBRATE FOR YOUR PHONE AND CASE A case or camera bump tilts the phone a little. Calibrate once: • Turn-around: read a spot, turn the phone end-for-end, read it again. Works on the roof itself. • Level surface: one reading on a surface you know is level. The app refuses a calibration that does not add up (a surface that is not level, or a phone that was not turned) and tells you when the case tilt is larger than usual. The calibration date is shown on the gauge. ▶ JOB READINGS Tap Add to job for each face — front, back, porch, garage. For the reading you pick, the Job page shows: • the common rafter / area factor and the hip / valley factor • minimum slopes by roof covering from the 2021 International Residential Code, section R905: asphalt shingles, clay and concrete tile, metal roof shingles, mineral-surfaced roll roofing, slate, wood shingles and wood shakes, each marked Below minimum, Allowed with double underlayment or Meets minimum, with the section number Checks use the unrounded value, so 1.9/12 is not passed as 2/12. The IRC is a US model code; local codes and the product's instructions can require more. ▶ SIGHT FROM THE GROUND Hold the phone up, camera on the roof, and turn it until the yellow line lies on the roof edge. The result is the apparent slope in the image and is labelled rough: it matches the real pitch only when you face the gable end square-on at about its height. No photo is taken or stored. ▶ ESTIMATE Send a reading to the estimator: rafter length, roof area, roofing squares and shingle bundles for a simple gable roof, hip / valley rafter length, waste and an optional material cost. Estimates saved in the earlier version stay in the list. ▶ PITCH TABLE AND GUIDE Common pitches from 1/12 to 18/12 with degrees, percent, rise per 10, rafter factor and the IRC minimum that starts at each one, plus a short guide to measuring safely. Readings come from the phone's sensor and depend on how flat the phone sits. Use them for planning, and check critical measurements with a level. Works offline, no account. Supported by ads: an ad may appear when you open the app, a banner is shown at the bottom, and a full-screen ad may follow a saved estimate. Sharing job readings or an estimate as text can be unlocked for 24 hours by watching an ad.