Satellite roof measurement has gone from a novelty to standard practice in roofing over the last decade. Insurance adjusters use it. Supplement contractors depend on it. Storm restoration companies run measurements before they ever knock a door. Here's how the technology actually works, which providers offer what, and how accurate it really is.
How Satellite Roof Measurement Works
The term "satellite measurement" is slightly misleading — most providers use high-resolution aerial imagery from aircraft and drones, not satellite-grade imagery. The process works like this:
- Image capture: Aerial imagery of the property is captured from a plane or drone flying at low altitude. Most major providers capture imagery of the United States at 6-inch or better resolution on a regular update cycle.
- 3D modeling: The system uses stereo imagery (multiple photos from slightly different angles) and computer vision to build a 3D model of the roof geometry.
- Facet identification: The AI identifies each individual roof facet — each distinct plane of the roof. For a simple gable, that's 2 facets. A complex hip roof with dormers might have 20+.
- Measurement calculation: With the 3D model and known image scale, the system calculates area, slope, and linear measurements (ridge, hip, valley, eave, rake) for each facet.
- Report generation: The output is a report showing total roof area, area by facet, and all linear measurements — usually delivered as a PDF and/or data file.
Major Providers Compared
EagleView
The market leader for professional roofing and insurance use. EagleView has the widest coverage, the most established accuracy track record, and is the de facto standard for insurance adjuster reports. Reports are available for most U.S. addresses within hours.
- Cost: Per-report pricing, typically $15–$25 per residential report depending on volume and tier. Bulk pricing available.
- Best for: Insurance documentation, supplement disputes, situations where you need a report that adjusters will accept without question.
- Limitation: Per-report cost adds up at high volume. No subscription option for unlimited use.
Hover
Hover uses your smartphone camera to build a 3D model. You walk around the house taking photos from specific angles, upload them, and Hover generates a measurement report (plus a 3D visualization that can be used for virtual product presentation).
- Cost: Subscription-based; pricing varies by plan.
- Best for: Retail sales with a visual presentation component. The 3D model lets homeowners see what different shingle colors look like on their roof.
- Limitation: Requires someone to be at the property to take photos. Not viable for high-volume storm response where you're measuring many properties quickly.
Google Solar API (used by Ketterly)
Google's Solar API provides roof measurements and solar potential analysis using the same aerial imagery that powers Google Maps. It returns facet-by-facet measurements including area, pitch, and orientation.
- Cost: API pricing based on call volume; when integrated into a platform like Ketterly, it's included in the subscription at no per-report charge.
- Best for: High-volume measurement where per-report cost would be prohibitive. Unlimited measurements for companies running 20, 50, or 200 measurements per month.
- Limitation: Coverage is strong in most of the continental U.S. but thinner in rural areas. Not as widely accepted by insurance adjusters as EagleView for formal documentation (though the data quality is comparable).
Accuracy: What the Research Shows
Multiple independent studies have validated EagleView's accuracy against manual measurement:
- A study published in the Journal of Applied Remote Sensing found EagleView accuracy within 1–3% for total roof area on standard residential properties.
- Internal validation studies by EagleView and independent contractor evaluations typically report accuracy within ±5% for complex roofs.
- Google Solar API accuracy has been benchmarked against EagleView in multiple roofing software comparisons, with results generally comparable for standard residential geometry.
What does ±5% mean for your estimate? On a 25-square job, a 5% error is 1.25 squares — about $120–$200 in material cost. Given that you're adding a 10–15% waste factor anyway and rounding up to whole squares, the practical impact on your estimate is minimal for the vast majority of jobs.
Where Satellite Measurement Struggles
Even the best satellite measurement has known failure modes:
- Tree canopy: Heavy tree coverage over the roof blocks aerial views and can cause missed facets or incorrect area calculations.
- Outdated imagery: If a property has had additions, dormers added, or major renovations since the last imagery update, the report reflects the old roof, not the current one. Imagery update cycles vary — urban areas are updated frequently; rural areas may have older data.
- Very flat pitch: On near-flat residential roofs (2/12 or less), the 3D modeling is less precise because there's less angle information in the stereo images.
- Custom architecture: Turrets, curved sections, complex custom geometry may be measured incorrectly. These require manual verification.
- Multi-structure properties: Make sure the report is for the correct structure if there are multiple buildings (detached garage, barn, outbuilding).
How Roofing Companies Use It Operationally
Storm canvassing
A rep is at the door. The homeowner is interested but wants a ballpark number. The rep pulls up a satellite measurement on their phone, gets the square count in 30 seconds, and can give a range right there. No second appointment, no "let me go back to the office and run numbers."
Pre-qualifying remote leads
Before driving 45 minutes to a property, run a satellite measurement to verify the roof size and complexity. If it's a small, simple roof that won't support a profitable job, you know before you go.
Insurance supplement documentation
EagleView reports are accepted as evidence in supplement disputes with adjusters. Having a professional report with linear measurements (ridge, valley, rake) is more defensible than a contractor's handwritten tape measure results.
Accurate estimating at scale
During storm season, a company estimating 30–50 properties per day cannot physically measure every roof. Satellite measurement makes that volume possible — with accuracy that's more than sufficient for initial estimates.
Cost-Per-Measurement Math
If you're running 50 measurements per month and paying $20 per EagleView report, that's $1,000/month in measurement costs — before you account for the ones that don't convert to jobs. If your close rate is 35%, you're spending $2,857 in measurement costs per closed job.
For companies at that volume, an unlimited measurement solution (like what's built into Ketterly) changes the math fundamentally — you can measure every inquiry, every door knock, every referral without thinking about cost per report. That changes behavior: estimators measure more liberally, which means more accurate proposals and fewer surprises.
Further Reading
- Complete Guide to Roofing Estimates — How measurement fits into the full estimate workflow from square count to signed proposal
- Satellite vs Manual Measurement — When each method wins and how to use them together for the most accurate estimates
- Ketterly for Storm Restoration Contractors — Unlimited satellite measurement included for storm companies that can't afford per-report costs at scale