How do satellite roof measurements work?

Satellite roof measurement software reads two things: an overhead photograph, and a digital surface model — an elevation value for each point on the ground, including the roof above it. The photograph alone cannot give a pitch, because a photograph has no height; the elevation model is what turns a flat outline into a three-dimensional roof with slopes.

Orbit extracts the roof surface from that elevation model, separates it into individual facets where the slope changes, and calculates each facet's area and pitch. The pitch is then calibrated against a second independent source for the same building, so a noisy elevation reading cannot quietly produce a wrong slope for the whole roof. Edges are classified by how they sit against neighbouring facets — an edge where two slopes meet at the top is a ridge, an edge running up the slope is a rake, an edge across the bottom is an eave.

A roof measurement report contains the roof's total area, its area in squares, the predominant pitch, and the linear footage of every edge type — because those edge lengths, not the area, are what price the drip edge, ridge cap, valley metal and starter course on an estimate.

In Orbit those figures are wired straight into the estimate: a line item is mapped to a metric — ridge cap to ridges plus hips, drip edge to eaves plus rakes — and its quantity fills itself in from the linked report, divided by the coverage of the purchase unit and multiplied by the waste factor. Re-typing measurements into a price sheet is where estimating mistakes come from.

Satellite roof measurements are least accurate on attached buildings, on roofs with deep overhangs, and anywhere the underlying imagery or elevation data is old or missing. These are properties of the data every vendor builds on, not of one product, and a vendor who claims otherwise is describing marketing rather than geometry.

The specific cases worth knowing before quoting from one:

• Attached townhomes and row buildings are frequently recorded as a single structure, so an automatic measurement can return the whole terrace rather than the one unit being quoted.
• Deep overhangs, carports and porches can sit outside the modelled building footprint and be trimmed off, producing an under-measure.
• New construction and rural addresses often have no elevation coverage at all, in which case there is nothing to measure from and the address falls back to a different data source.
• Complex commercial roofs with many facets are where automatic geometry degrades fastest and a human-checked report earns its cost.

Orbit's instant measurement clips to the building under the pin specifically to avoid pulling a neighbouring structure into the total, and it reports the area, pitch and edge lengths it derives rather than drawing a facet diagram, because the free elevation data behind the instant tier is not clean enough to draw a diagram a contractor should trust. The human-certified report does include the full diagram.

An instant roof report is generated by software in seconds and costs $2.37 in Orbit; a certified report is produced and checked by a human technician, costs $15.76 on a paid plan, and arrives a little later. The instant report is for qualifying a lead quickly; the certified report is for a roof you are about to price, order material for, or submit to an insurer.

Measurements are billed per report rather than bundled into the subscription, so there are no minimums and no measurement credits to buy up front — a slow month costs nothing. What roofing CRM software costs compares those per-report prices against what other vendors publish.

Yes — Orbit includes unlimited hand tracing on satellite imagery on every plan, including the free one. Tracing a roof by hand means outlining each facet on the aerial photograph and marking which edges are eaves, ridges, hips, valleys and rakes; the software converts the outline to real dimensions and calculates the same area, pitch and linear footage an ordered report would give.

There is no calibration step — the scale is derived from the map itself, so a traced roof is measured the moment the outline closes. The trade-off is your time: hand tracing a simple roof takes a few minutes, which is worth it on a quiet afternoon and not worth it when a report costs $2.37.

A satellite measurement replaces the tape measure, not the inspection. It will tell you the area, pitch and edge lengths accurately enough to order material, and it cannot tell you that the decking is soft, the flashing was never replaced, or there are three layers underneath — all of which change the price more than a square either way.

The practical use is sequencing: measure from the desk to price and present, then inspect the roofs worth inspecting. That is the difference the measurement makes — not skipping the ladder, but not carrying it to every address that was never going to buy.