When the drawings do not match reality
Most buildings have drawings. Far fewer have drawings that actually describe the building as it looks today. After decades of renovations, extensions and small adjustments, the gap between archive and reality is usually wider than the owner thinks, and it tends to surface exactly when a new project starts.
What the gap costs
Outdated drawings lead to incorrect quantities, clashes during design and change orders during construction. Individually they are manageable; together they can wreck a schedule. The most expensive surprises often come from things that have "always been there" but never made it onto paper.
Scanning as the starting point
An as-built drawing produced from scan data describes the building as it is now, not as it was drawn. Walls land where they actually stand, penetrations are documented, services are visible. The result is a stable basis for everything that follows, design, facility management and future refurbishment.