How to measure a roof from satellite imagery

You measure a roof from satellite imagery by tracing each roof plane on an aerial view and letting the tool calculate the area. With Quove you click the corners of every plane, the polygon follows your points, and the square footage appears as you work. Here is how to get a number you can bid from.

Square up the imagery first

Center the property and zoom in until the roof fills most of the frame. The closer you are, the more precisely you can place each corner. Take a moment to spot the separate planes, the hips, valleys, and dormers, before you start tracing.

Trace one plane at a time

Roofs are rarely one flat rectangle. Trace each plane as its own shape so the area reflects the real surface, not a flattened footprint. A simple gable has two planes; a cut up roof can have a dozen.

Account for pitch

Satellite imagery looks straight down, so it captures the footprint, not the slope. A steep roof has more surface than its footprint suggests. Apply a pitch multiplier to your measured area, or build the typical pitch into your rate, so the bid covers the real material.

• Tracing the gutter line instead of the roof edge, which undercounts the overhang.
• Skipping small planes over porches and bay windows that still need shingles.
• Forgetting that a flat footprint understates a steep roof.

Once the planes are traced and the pitch is accounted for, the square footage is ready to price. Multiply by your roofing rate and the estimate is done, all without a ladder.