Clash Detection Best Practices for MEP Systems

Misaligned models create false clashes and missed conflicts.

Not separating tests by zone makes it harder to prioritize real problem areas.

Treating all clashes equally delays resolution of critical installation blockers.

Not separating tests by zone makes it harder to prioritize real problem areas.

Clash Detection Best Practices for MEP Systems

Successful BIM clash detection for MEP systems is not just about running software; it’s about building a repeatable coordination process that reduces noise, speeds resolution, and improves constructability. The following best practices help teams get consistent, high-quality results across project phases.

1) Validate Model Readiness Before Running Clash Tests

Clash detection should never begin on incomplete or misaligned models. Start with a basic BIM QA/QC check:

1. confirm shared coordinates and alignment
2. verify levels, grids, and model units
3. enforce naming conventions (systems, zones, levels)
4. check model completeness and appropriate LOD for coordination

Without this step, teams generate excessive false positives and miss real conflicts—undermining the value of MEP clash detection services

2) Use a Clash Detection Matrix to Define What Gets Tested

A clash detection matrix sets the “rules of engagement” by defining:

1. which systems are tested against each other
2. which elements are excluded (hangers, insulation, small fittings, etc.)
3. tolerance settings for clearances and access zones
4. priority order for resolution

This prevents teams from wasting time on low-value clashes and keeps coordination focused on high-impact conflicts.

3) Coordinate the Largest Systems First

A proven rule in MEP coordination is to resolve “big geometry” first:

1. structural constraints + ceiling zones
2. duct mains and major HVAC distribution
3. pipe mains (chilled water, domestic, drainage, etc.)
4. cable trays and major electrical distribution
5. branches, flex connections, and minor reroutes

This hierarchy reduces rework cycles and supports efficient MEP shop drawing development

4) Include Soft Clash Checks for Maintenance and Code Clearance

Hard clashes alone don’t prevent field issues. Many operational problems come from clearance and access violations. Add soft clash rules for:

1. valve access zones and service clearances
2. electrical panel working clearances
3. equipment maintenance envelopes
4. insulation allowances and pipe spacing
5. required code separation zones (where applicable)

These checks ensure models are installation-ready, not just visually clash-free—especially important for healthcare, data centers, and mission-critical facilities

5) Run Targeted Clash Tests by Zone

Avoid one massive clash run that generates thousands of clashes. Instead, structure Navisworks clash detection by:

1. floors, corridors, shafts, and mechanical rooms
2. priority zones (high-density areas first)
3. system-specific tests based on the clash matrix

This improves clash triage and makes coordination meetings more efficient.

6) Use Grouping and Filtering to Reduce Clash Noise

Clash tools often generate duplicates. Use grouping and filtering to:

1. remove repeated clashes caused by overlapping geometry
2. group clashes by room/level/system
3. isolate conflicts that impact critical paths
4. filter out low-value element clashes (e.g., tiny fittings)

This makes the clash detection report practical and actionable.

7) Assign Ownership and Track Issues in a Central System

Clash detection succeeds only when issues are resolved and verified. Every clash should have:

1. assigned owner (trade/discipline)
2. deadline + priority level
3. status tracking (open/in progress/closed)
4. evidence of resolution (updated viewpoint + comment)

Use issue tracking for BIM coordination via ACC/BIM 360, BCF workflows, or coordination platforms like Revizto.

8) Make Clash Detection a Continuous Process

Clash detection is iterative. Run clash checks at defined project milestones and regularly during design development. Continuous review prevents last-minute overload and supports faster closeout.

How to Prioritize and Resolve MEP Clashes Faster

Clash detection works only when issues are resolved quickly and verified. The fastest way to improve closeout is to prioritize clashes using a clash matrix and resolve them in a consistent sequence.

Use a 3-Level Priority System

• Critical: impacts structure, life safety, code clearances, or main distribution (duct/pipe/tray)
• Major: affects routing, access, performance, or installation feasibility
• Minor: small overlaps with minimal downstream impact

Resolve in the Right Order

Coordinate in this sequence to reduce rerouting cycles:

1. Structure/Architecture
2. Duct mains
3. Pipe mains
4. Cable trays
5. Branches

Reduce Noise and Speed Closeout

• group clashes by zone (floor, shaft, corridor, mech room)
• remove duplicates and false positives
• focus on high-density areas first

Assign Ownership and Verify

Each clash must have an owner, due date, viewpoint/screenshot, and re-test confirmation. Tools like ACC/BIM 360, Revizto, or BCF workflows help track progress and prevent re-open cycles.

Clash Reporting and Documentation Checklist

• Include Clash ID, type, severity, systems involved, and exact location
• Assign a clear owner and maintain an updated status
• Add a due date + resolution notes for every issue
• Attach a screenshot + saved viewpoint to every clash for fast review
• Group clashes by level + zone
• Use consistent naming
• Remove duplicates and false positives before publishing reports

How Tejjy Inc Supports Effective MEP Clash Detection and BIM Coordination

Tejjy Inc provides commercial BIM coordination services to help general contractors, MEP subcontractors, and design teams deliver clash-free, constructible MEP systems. Our team applies a proven MEP clash detection workflow using Navisworks Manage and Autodesk Construction Cloud (ACC/BIM 360) to identify hard clashes, soft clashes, and workflow/4D sequencing conflicts before they reach the jobsite.

We support commercial projects by setting model QA/QC standards, building discipline-specific clash detection matrices, and running targeted clash tests by zone, including ceiling plenums, corridors, shafts/risers, and mechanical/electrical rooms. Tejjy also delivers standardized clash detection reports, issue tracking, and closeout verification to reduce RFIs, minimize rework, and improve installation sequencing. The result is faster coordination cycles, stronger constructability, and installation-ready MEP models that keep commercial construction schedules predictable.