Clash Detection in Revit MEP: A Step-by-Step Guide

Table of contents

• Related Resources on Revit BIM
• What is Clash Detection in BIM?
  • Common Examples of Clashes in MEP
• Why Use Revit for Clash Detection in MEP?
  • Key Benefits
• Step-by-Step Guide: Clash Detection in Revit MEP
  • Step 1: Prepare Your Revit Model
  • Step 2: Access the Interference Check Tool
  • Step 3: Select Categories to Check
  • Step 4: Run the Clash Detection
  • Step 5: Review the Results
  • Step 6: Resolve the Clashes
  • Step 7: Export Clash Reports
• Advanced Clash Detection: Revit vs. Navisworks
  • Clash Detection in Revit
  • Clash Detection in Navisworks
• Best Practices for Clash Detection in Revit MEP
• Benefits of Clash Detection for Construction Projects
• Real-World Example
• Conclusion

In modern construction, coordination between multiple disciplines—architectural, structural, and MEP (Mechanical, Electrical, Plumbing)—is essential to prevent costly design conflicts and rework. One of the most powerful features of Building Information Modeling (BIM) is the ability to detect clashes before construction begins.

Among BIM tools, Autodesk Revit MEP plays a central role in designing, modeling, and coordinating MEP systems. Revit’s built-in Interference Check tool allows engineers to identify and resolve conflicts within a project, ensuring a smoother workflow across all trades. This step-by-step guide will walk you through how to perform clash detection in Revit MEP, best practices, and when to integrate advanced tools like Navisworks for complete project coordination.

Related Resources on Revit BIM

What is Clash Detection in BIM?

Clash detection is the process of identifying geometric conflicts between different elements in a 3D model. These conflicts—often referred to as "clashes"—occur when two or more building components occupy the same physical space. Detecting these early reduces delays, change orders, and budget overruns.

Common Examples of Clashes in MEP

• Mechanical clashes: Ducts running into beams or ceilings.
• Plumbing clashes: Pipes intersecting with walls, structural columns, or HVAC ducts.
• Electrical clashes: Cable trays or conduits conflicting with structural framing.
• Equipment clashes: Mechanical units placed in restricted spaces or blocking access zones.

Why Use Revit for Clash Detection in MEP?

While tools like Autodesk Navisworks are commonly used for advanced clash detection and coordination, Revit’s Interference Check tool provides a fast, in-model solution for engineers working directly in design.

Key Benefits

• Identifies design conflicts early in the modeling phase.
• Enhances collaboration with architects and structural engineers.
• Reduces errors and rework during construction.
• Saves costs by avoiding material wastage and delays.
• Provides reports for documentation and accountability.

Step-by-Step Guide: Clash Detection in Revit MEP

Step 1: Prepare Your Revit Model

• Open your Revit MEP project.
• Ensure linked architectural and structural models are loaded into your file.
• Set up proper worksets and views for easier coordination.

Tip: Always keep your models up-to-date with the latest linked files before running clash detection.

Step 2: Access the Interference Check Tool

Go to the Collaborate tab on the Revit ribbon. Under the Coordinate panel, select: Interference Check > Run Interference Check. This is the starting point for all clash detection activities within Revit.

Step 3: Select Categories to Check

Revit allows you to run interference checks between specific categories of elements. Examples:

• Ducts vs. Beams
• Pipes vs. Walls
• Cable trays vs. Ceilings
• Conduits vs. Structural Columns

Tip: Running checks system-by-system (rather than all at once) makes it easier to interpret results.

Step 4: Run the Clash Detection

After selecting your categories, click OK. Revit will process the model and generate a list of detected clashes. Each clash will include element IDs, categories, and a direct link to the location.

Step 5: Review the Results

Open the Interference Report dialog box. Click on each clash result to highlight it in the 3D model. Use the Zoom to Element option for a closer look.

This step is crucial for visually verifying whether the clash is a real issue or just a modeling overlap that doesn’t affect constructability.

Step 6: Resolve the Clashes

Once clashes are identified:

• MEP engineers can reroute ducts, pipes, or conduits.
• Structural engineers may adjust beam or column positions.
• Architects may modify wall layouts or ceiling heights.

Collaboration is key here. Revit’s Copy/Monitor tool helps ensure that linked elements remain aligned across disciplines.

Step 7: Export Clash Reports

Clash results can be exported in HTML format. Share the report with team members, contractors, or consultants for documentation. Keep a record of resolved vs. pending clashes for project tracking.

Advanced Clash Detection: Revit vs. Navisworks

While Revit’s built-in interference check is powerful, it is limited compared to Navisworks Manage, which provides more robust clash detection.

Clash Detection in Revit

• Checks clashes between two selected categories.
• Suitable for small to mid-size projects.
• Useful during the design phase.

Clash Detection in Navisworks

• Detects clashes across all categories and models simultaneously.
• Supports rule-based clash tests (e.g., ignore small tolerances).
• Generates detailed clash reports with comments, assignments, and status tracking.
• Best suited for large-scale projects and multi-disciplinary coordination.

Best Practice: Use Revit for design-phase clash detection and Navisworks for construction-phase coordination.

Best Practices for Clash Detection in Revit MEP

1. Run Checks Regularly – Don’t wait until the end of the design; perform clash checks during major design milestones.
2. Isolate by Systems – Check HVAC, plumbing, and electrical separately for better clarity.
3. Use Coordination Views – Create 3D views with color overrides to visually highlight clashes.
4. Set Tolerances – Avoid reporting minor overlaps that don’t impact constructability.
5. Collaborate Early – Share clash results with architects and structural teams as early as possible.
6. Document Everything – Export reports for accountability and project record-keeping.

Benefits of Clash Detection for Construction Projects

• Reduced Site Conflicts: Detecting issues early avoids construction stoppages.
• Cost Savings: Prevents material waste and rework costs.
• Time Efficiency: Keeps projects on schedule by reducing unexpected delays.
• Improved Collaboration: Enhances communication between all stakeholders.
• Higher Quality Models: Results in better-coordinated, more reliable designs.

Real-World Example

Imagine a hospital project where HVAC ducts are routed across multiple floors. During clash detection in Revit MEP:

• Engineers discover ducts intersecting with structural beams in multiple locations.
• By running interference checks early, the design team reroutes ducts, adjusts ceiling heights, and coordinates with structural engineers.
• This proactive resolution saves weeks of potential construction delays and thousands in cost overruns.

Conclusion

Clash detection is one of the most powerful quality-control features in Revit MEP. By using the Interference Check tool, MEP engineers can quickly identify design conflicts, resolve them with other stakeholders, and ensure smoother project execution. When combined with tools like Navisworks, clash detection becomes a comprehensive process—spanning from the design stage to construction coordination.

Key takeaway: Running clash detection regularly in Revit MEP leads to fewer errors, better collaboration, and successful project delivery.