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Coordination means more than finding clashes.

We review discipline models together beyond geometric clashes, considering access, maintenance, installation, tolerances, openings and site constructability.

The aim is not simply to reduce the clash count, but to develop a coordinated project that can be built on site.

Clash-free does not necessarily mean constructible.

Two elements may have no geometric clash, yet access, maintenance space, working clearance or servicing requirements can still make the solution impractical on site.

Coordination must consider geometry, access and operational requirements together.

Vertical pipework and a cable tray restrict maintenance and servicing space for mechanical equipment despite the absence of a physical clash.
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The layers of coordination

Model-based coordination is more than checking geometric clashes. Multiple layers of review are considered together, extending through to site constructability.

Five coordination layers with their model-based checking topics.
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  1. 01

    Geometric coordination

    • Physical clashes
    • Penetrations
    • Openings
  2. 02

    Functional coordination

    • Access
    • Maintenance space
    • Working space
    • Servicing requirements
  3. 03

    Installation coordination

    • Installation sequence
    • Hangers / supports
    • Prefabrication
    • Site access / installation
  4. 04

    Discipline interfaces

    • Architecture – MEP
    • Structure – MEP
    • Infrastructure – Site
    • Equipment – Building
  5. 05

    Revision and decision management

    • Issue
    • Owner
    • Status
    • Decision
    • Closure

Coordination starts with a shared model environment.

Overlaying discipline models is not enough for federation. Models must be reviewed together within a shared structure for location, version, discipline and coordination.

Source models

  • Architectural
  • Structural
  • Mechanical
  • Electrical
  • Infrastructure
  • Site
Six discipline models combined into a federated model using shared coordinates, versions and reference checks.
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Federation checks

  • Shared coordinate system
  • Model version
  • Discipline separation
  • Link / reference checks
  • Model scope
  • Shared coordination view

Federation is not simply overlaying models. It establishes a shared structure in which they can be reviewed reliably together.

Identifying clashes early

Geometric clash checks are a fundamental part of coordination, but they do not cover the entire process on their own.

  • Hard clash
  • Clearance / soft clash
  • Opening / penetration issues
  • Duplicate / overlapping geometry
  • Critical clearances between systems

Fitting in the model does not mean it can be built on site.

Three constructability examples: maintenance/access space, transport/installation route, and tolerances/openings.
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01

Maintenance / access space

The equipment service panel opens, but another system occupies the servicing volume.

02

Transport / installation route

The element fits in its final model position, but cannot be transported or installed there on site.

03

Tolerance / openings

A pipe or duct theoretically passes through an opening, but the necessary installation clearance and tolerance are missing.

Constructability review considers whether an element is accessible, installable and workable with its tolerances, rather than simply whether it “fits” in the model.

Coordination is not a one-off check.

Identified issues are classified, assigned to the relevant discipline, resolved and checked again after revision.

Issue identification, classification, assignment, resolution, rechecking and closure, with revision records.
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  1. 01Identify
  2. 02Classify
  3. 03Assign
  4. 04Resolve
  5. 05Recheck
  6. 06Close

Issue information

  • ID
  • Discipline
  • Location
  • Description
  • Owner
  • Status
  • Revision
  • Date

Coordination is a decision-making process tracked through successive revisions.

How does the coordination process work?

  1. 01

    Model acceptance and review

    Version, coordinates, scope and model health.

  2. 02

    Federation

    Combine discipline models in a shared environment.

  3. 03

    Clash rules

    Define the checking sets.

  4. 04

    Constructability review

    Access, maintenance, installation, tolerances and openings.

  5. 05

    Issue creation

    Location, description, discipline and owner.

  6. 06

    Discipline resolution

    The relevant teams revise their models.

  7. 07

    Revision review

    Verify that the solution is correctly incorporated into the model.

  8. 08

    Closure and reporting

    Issue closure, coordination status and tracking records.

Coordination deliverables

  • Federated model
  • Clash / coordination report
  • Issue register
  • Coordination views
  • Marked-up screenshots
  • Constructability notes
  • Revision tracking
  • Coordination meeting records

Deliverables are defined by the project scope and coordination requirements.

Model-Based Technical Deliverables →BIM Process & Data Management →

Our coordination environments

Software / platforms

  • Autodesk Revit
  • Navisworks
  • Autodesk Construction Cloud
  • IFC / openBIM

Where required

  • BCF / issue exchange
  • Custom checks
  • Automation

Site realities inform coordination decisions.

DFL reviews models beyond digital geometry, considering constructability, access, maintenance, installation and site conditions.

BIM informed by the site.

BIM Modeling →
DFL / BIM Coordination & Constructability Review

The purpose of coordination is not simply fewer clashes, but a project that can be built on site.

Let’s assess your project