The short answer
Terrestrial laser scanning is the inside-the-envelope tool. Drone photogrammetry is the outside-the-envelope tool. If your question is about pipe, structure, above-ceiling MEP, or equipment clearance, you want terrestrial laser scanning. If your question is about roof area, yard grading, stockpile volume, or a whole campus, you want drone mapping. Many industrial projects need both, captured into one control network.
The mistake we see most often is paying for the wrong instrument because the sales conversation started with the technology instead of the decision. A roof quantity takeoff does not need millimeter-class LiDAR. A pipe tie-in cannot be measured from an orthophoto.
Photogrammetry vs LiDAR for buildings
Photogrammetry derives 3D geometry from overlapping images. It is excellent on textured, well-lit surfaces: roofs, façades, yards, stockpiles. It struggles with featureless surfaces, deep shadow, reflective glass, and anything it cannot see from the air.
LiDAR measures range directly with a laser, so it does not care about texture or ambient light. Terrestrial LiDAR gives the density and repeatability that engineering-grade as-built documentation depends on. UAV LiDAR sits between the two: useful for corridors, vegetated sites, and large outdoor areas where you need ground under cover.
- Interior geometry, MEP, pipe rack scanning, clash detection — terrestrial laser scanning
- Roof photogrammetry, orthomosaic mapping, stockpile volume, site topography — drone mapping
- Vegetated corridors and large outdoor sites — UAV LiDAR survey
- Marketing visuals and remote orientation — a walkthrough, not a survey
Matterport vs laser scanning
Virtual walkthroughs are genuinely useful for orientation, remote walkdowns, and showing a space to people who will never open CAD. They are not an engineering-grade measurement product, and treating a walkthrough as an as-built survey is how dimensions end up wrong on a fabrication drawing.
We are happy to deliver a walkthrough alongside a registered point cloud. What we will not do is let one stand in for the other when the deliverable feeds design, fabrication, or construction verification.
Accuracy expectations
Typical terrestrial laser scanning field accuracy is ±2–6 mm, depending on range, incidence angle, surface, control, and registration quality. Drone photogrammetry accuracy is driven by ground sample distance and ground control: with surveyed targets and RTK or PPK positioning, centimetre-level results on hard surfaces are realistic.
Any provider who quotes a single accuracy number without asking about your site is quoting a brochure. We deliver an RMSE and registration report so the number can be checked rather than believed.