What a drone survey actually captures
Three deliverables: (1) Orthomosaic — a flat, top-down aerial photo at sub-cm accuracy. (2) 3D model — every roof contour, slope, obstacle captured in a CAD-importable point cloud. (3) Thermal scan — identifies hotspots, water ingress, insulation gaps. Total flight time: 12–18 minutes for a typical commercial roof. Total processing time: 48 hours.
What you'd miss with a ladder survey
Five things a ladder can't tell you: (1) Exact roof slope to 0.5° (matters for tilt design). (2) Exact panel layout possible without physical clamping test. (3) Cable run distances — affects DC string losses. (4) Plant locations on roof (lift overruns, smoke vents, condenser units). (5) Shading patterns from neighbouring buildings at different sun angles.
The structural assessment angle
Drone delivers a structural baseline — roof condition, ponding evidence, missing flashings, areas of obvious damage — without anyone going on the roof. The structural engineer then uses this + the building specification to determine load capacity. On older portal-frame buildings, that baseline is often what flags frames needing reinforcement before any panels go on.
CAA Part 107 / GVC certification
Drone surveys on commercial sites need a CAA-certified Remote Pilot. KMM uses GVC (General VLOS Certificate) operators — required for flight over residential or industrial areas. We also carry £5M public liability and £2M aviation insurance on every flight.
Why we don't use Google Earth
Google Earth resolution is 1m per pixel in most UK areas — useful for area estimation, useless for design. We've seen quotes built off Google Earth that miss skylights, AC condensers, and roof-top plant. KMM drone survey resolves to ~5mm per pixel — every detail captured.
The data ends up in CAD
The 3D model exports to DWG/RVT/SketchUp formats. Our PV designers use it directly to lay out panels with 5mm clearance from edges, automatic shading analysis on the actual geometry, and accurate cable routing. No surprises on installation day.
How drone surveys cut install time
Pre-drone era: install crew arrives, discovers roof anomaly, calls designer for redesign, half-day lost. Post-drone era: every cable, panel, clamp position pre-planned. On large roofs that is the difference between a redesign on the day and a layout that simply gets built.
Free drone survey: how KMM funds it
KMM offers free drone surveys on any commercial site over 30 kWp inquiry size. Why we can do this: drones are now ~£8k assets, GVC pilots cost ~£250/day, processing software is ~£1,200/year. Total per-survey cost: £400–£800. We absorb this against the install margin if we win the job. No survey fee, no obligation.
