BIM coordination is the process of combining every trade’s 3D model — structure, architecture, mechanical, electrical, plumbing, fire protection — into one federated model, finding the places where those trades physically conflict, and resolving them before the work reaches the field. The output isn’t a model. It’s a building that goes together as drawn, with the expensive surprises caught while they’re still a screen edit instead of a change order.
That’s the definition. What most people actually want to know is what the process looks like — what happens between “we’re starting coordination” and “the field can build this.” I run live BIM coordination today on active multifamily work, so here’s the real weekly rhythm, step by step. (If you’re asking about the person rather than the process — what to expect from the role itself — I wrote up what a BIM coordinator actually does separately.)
Kickoff: agreeing how the job will be coordinated
Before the first clash test runs, the team agrees on the ground rules: how the building splits into coordination zones (by level, by area, by pour), what each trade is expected to model and to what level of detail, which conflicts belong to coordination versus the field, and the meeting cadence — almost always weekly. Skipping this step doesn’t save time; it just moves the arguments into week six, when they’re harder to fix.
This is also where the schedule enters. Coordination isn’t open-ended — each zone has to be coordinated, signed off, and released ahead of fabrication and installation. The coordination schedule runs in front of the construction schedule, and staying in front of it is the whole game.
The weekly cycle
From kickoff to the last sign-off, coordination runs the same loop every week. On the work I run, the models and the full issue log live in Autodesk Construction Cloud (ACC), where the GC, the trades, and the design team can open the current model in a browser anytime — nothing about the process is a black box.
1. Trades post current models. Every detailer uploads their latest — mechanical, electrical, plumbing, fire protection — on a set day. Late or stale models get chased immediately, because coordinating against last month’s model produces confident, useless answers.
2. Federate and run clash detection. The trade models get combined into one federated model and run against each other. The software flags every place two objects occupy the same space — on a real project, that’s hundreds or thousands of hits per run.
3. Triage: sort the real conflicts from the noise. This is the judgment step. A hanger grazing an insulation wrap is noise the trades absorb without a thought. A duct through a beam, a main with no clearance to service the valve, a rack that blocks the only chase — those stop the field. Triage sorts the list into what actually matters, prioritizes it (structural and concrete conflicts first, because they’re the least forgiving), and packages it so the meeting spends its hour on the twenty conflicts that count, not the two thousand that don’t.
Clash software finds every overlap on the job. The process only works when someone sorts the twenty that would stop the field from the two thousand that won’t.
4. The coordination meeting. Weekly, one hour, agenda in the same order every time: overdue items first — by name, with the responsible trade on the call — then new critical conflicts, then area-by-area progress toward sign-off. Decisions get made in the meeting: who moves, which routing wins, what goes to the design team as an RFI when the model can’t answer the question on its own.
5. Assignments with hard deadlines. Every open conflict leaves the meeting owned by a specific trade with a specific date. This is where coordination either has teeth or doesn’t — an unowned conflict is construction that can’t proceed, quietly aging until it costs schedule.
6. Re-check and sign off, zone by zone. Resolved conflicts get re-run to confirm the fix didn’t create a new problem, and when a zone runs clean, each trade signs off on it — a commitment that says we can build our work in this area as modeled. Signed-off zones release to shop drawings and fabrication. Then the cycle starts again on the next zone.
The deadline that can’t slip: concrete
Every coordination item has a deadline. Concrete has a permanent one. Anything that penetrates or gets buried in structural concrete — sleeves, block-outs, embeds, in-slab conduit — has to be coordinated, signed off, and placed before the pour. Miss it, and the options are core-drilling around rebar you’d rather not touch (with an engineer’s blessing), or worse, rework in cured structure.
I spent a year of my career focused almost entirely on this — early block-out and sleeve coordination ahead of pour schedules on major projects — and it shaped how I run every job since: concrete-affecting conflicts jump the queue, always. It’s the least glamorous part of BIM coordination and the single highest-leverage discipline in it, because concrete is the one trade you can’t ask to move later.
How everyone stays honest: the weekly report
The cycle above only holds if everyone can see it. Beyond the live ACC model and issue log, I produce an AI-leveraged weekly coordination report — meeting minutes, clash status, and overdue conflicts distilled into one document a project manager can read in five minutes, with the overdue items tracked by trade so accountability is visible, not implied. “AI-leveraged” means technology assembles the document quickly and consistently; I review every line and make every call before it goes out. Nothing ships blind.
When coordination ends
Coordination winds down zone by zone, not all at once: each signed-off area releases to fabrication while later areas are still cycling. By the time the field reaches an area, its conflicts were resolved weeks or months earlier — which is the entire point. The meetings end; the value shows up as the changes that never got ordered.
One last distinction worth knowing before you staff it: the process only works as well as the person driving it, and where that person sits matters — same time zone, same language, same accountability. If you’re weighing an outside coordinator against an offshore production shop, this read on US-based vs. offshore BIM coordination walks through the trade-offs honestly.
Frequently asked questions
What is BIM coordination in one sentence?
It's the weekly process of combining every trade's 3D model into one, finding where the trades physically conflict, and driving those conflicts to resolution and sign-off before the work is fabricated or installed.
When should BIM coordination start?
Early enough that the answers still influence procurement and fabrication — typically alongside late design and preconstruction, and well before structure. The immovable marker is concrete: anything cast into or through it must be coordinated before the first affected pour.
How long does BIM coordination run on a project?
It tracks the construction schedule, zone by zone — months on most commercial projects, not weeks. The cadence is almost always a weekly cycle, and the effort front-loads around structure and the most congested MEP areas.
Who attends a BIM coordination meeting?
The coordinator running it, a detailer or BIM lead from each MEP trade, and the GC's project team — typically the PM or project engineer, with the superintendent's input on means and methods. The design team joins when RFIs need their call.
Does BIM coordination replace coordination in the field?
No — it removes the expensive category of field coordination: the physical conflicts that trigger rework, re-fabrication, and schedule loss. The field still owns means, methods, and the small stuff trades have always worked out shoulder to shoulder. If you're deciding who should run it, the honest trade-offs are in my US-based vs. offshore BIM coordination piece here on the blog.