Revit Tip: Duct Routing Best Practices and Fabrication Workflow

For reliable airflow, clean documentation, and shop-ready deliverables, route ducts with appropriate fittings and switch to Fabrication parts when construction-level detail is required.

• Start with sound system logic
  • Assign connectors correctly on equipment and terminals (System Classification, Flow Direction, Loss Method).
  • Enable calculations: Manage → Mechanical Settings → Duct Settings → Calculations = All.
  • Use the System Inspector to verify connectivity, flow accumulation, and pressure losses before refining geometry.
• Set routing preferences to drive the right fittings
  • Edit each Duct Type → Routing Preferences to specify elbows, tees, taps, crosses, and transitions.
  • Prefer radius elbows over mitered for lower pressure loss; limit branch takeoff angle (e.g., 45°) for smoother flow.
  • For trunk-and-branch layouts, choose taps instead of tees in Branch to reduce turbulence on the main.
  • Standardize sizes, materials, insulation, and lining in Type properties to keep schedules consistent.
• Route with accuracy and intent
  • Use the Connect Into and Trim/Extend tools to let Revit place the correct fitting automatically.
  • Control justification (Center/Top/Bottom/Left/Right) to align with structure and ceiling zones.
  • Model at real elevations with clearances; use section boxes in 3D to maintain spatial discipline.
  • Leverage Placeholder Ducts early, then Convert to quickly iterate without committing to fittings prematurely.
• When to switch to Fabrication Parts
  • Use Fabrication Parts for shop-level content, spooling, and CAM workflows. Set your Fabrication Configuration in Manage → MEP Fabrication.
  • Select the proper Service and Specification so straights, elbows, dampers, and accessories follow shop standards and size-rounding rules.
  • Convert design duct to fabrication with Design to Fabrication for consistent parts and data.
  • Use Route and Fill to bridge gaps between end conditions while complying with the chosen Service.
  • Create spools and use hangers from the Fabrication toolset to progress directly to coordination and fabrication.
• Coordination and QA
  • Keep runs consistent—don’t mix design duct and Fabrication Parts within the same segment.
  • Apply realistic loss methods on fittings (e.g., coefficient tables) to trust pressure drop results.
  • Run interference checks and federate in Navisworks for clash detection; get Navisworks via NOVEDGE.
  • Document with View Templates (MEP coordination, shop, and install views) to standardize graphics and review.
• Performance and maintenance
  • Resolve warnings early; mismatched connectors and open systems degrade both analysis and routing.
  • Purge unused fittings and consolidate family types to keep models fast and stable.
  • Use worksharing best practices—Synchronize with comments and Compact Central regularly.

If you’re building a repeatable workflow—templates, routing preferences, and Fabrication configurations—partner with NOVEDGE for licensing, configuration guidance, and add‑ons that enhance Revit MEP productivity. Explore Revit, Navisworks, and related tools at NOVEDGE.