BIM clash detection — where coordination meets design.

Most teams encounter clash detection as a late-stage activity — a report generated just before a stage submission to confirm that the model is roughly coordinated. That framing turns a powerful process into a formality, and it misses almost everything that makes clash detection worth running in the first place.

The value of a clash cycle isn't in the report. It's in what happens between the report being issued and the next one being run. When clash cycles are embedded weekly into the design programme, discipline leads are forced to make coordination decisions continuously rather than deferring them to a single crunch at the end of each stage. Those decisions are smaller, cheaper, and faster to resolve early — and they compound in quality as the design develops.

The setup matters more than the software. Any clash detection tool will find geometric intersections. What separates a useful clash report from an unusable one is the tolerance settings, the discipline groupings, and the decision about which clash types warrant a coordination issue versus which are acceptable overlaps. Without those calibrated upfront, a report of 800 clashes on a mid-size MEP model will grind a coordination meeting to a halt without resolving a single one.

We structure clash reviews around clearance zones, not geometry. A duct that passes 20mm clear of a structural beam is a passing coordination check on most projects. The same duct at 5mm clearance in a healthcare corridor — where maintenance access is a compliance requirement — is a coordination failure regardless of whether it geometrically intersects. Clash detection has to be configured around what actually matters on that specific project, not a default setting applied uniformly.

The output of a well-run clash cycle isn't a PDF. It's a set of agreed coordination decisions that feed back into the discipline models before the next round. When that loop works, the model gets more coordinated with each cycle rather than accumulating a growing backlog of deferred issues.