Point cloud / laser scanning

A laser scanner sweeps a scene and returns a point cloud: dense, accurate 3D coordinates of every surface in view. Scans from many positions are registered into one cloud covering a unit or a site, and the result is the closest thing brownfield work gets to ground truth — new design routed through the cloud, clashes checked against reality rather than against as-builts of uncertain honesty, and dimensional questions answered from the desk instead of the scaffold. Where the documentation gap is the brownfield tax, scanning is how the tax is paid deliberately instead of accidentally.

The honest limits: a cloud is geometry without meaning. It contains no tags, no line numbers, no topology — a pipe in the cloud is a tube of points until a human or an algorithm says which line it is — so scan-to-model is interpretation labour, priced accordingly, and usually scoped to what the project needs rather than everything the scanner saw. Coverage has shadows — behind equipment, under insulation, inside anything — and insulated lines are measured at the cladding, not the pipe. The cloud tells the truth, completely, about surfaces it could see; everything else is still inference.