HVAC shop drawings: what goes on them and how to make them in Revit
What an HVAC shop drawing contains and how to produce one in Revit. Duct sizes, elevations, fittings, accessories, air terminals, equipment, insulation, and the tags that tie them together. See where RayCAD fits.
On this page
An HVAC shop drawing is the drawing the sheet metal crew builds from and the foreman installs from. It carries every duct size, every elevation, and every damper, and it has to match the schedule and the model.
This guide covers what goes on one, and how to make one in Revit. RayCAD is our Revit plugin for MEPF annotation. Tagging is the largest manual step on these sheets, and under each part of the drawing you will see what it costs by hand and what RayCAD does.
What goes on an HVAC shop drawing?
Vendor descriptions and the common practice list the same items.
- Ducts. Size, routing, elevation, and length where the shop cuts to order.
- Fittings. Elbows, tees, transitions, and the others, identified and sized.
- Accessories. Dampers, silencers, access doors, and flex connectors, with marks and, for fire dampers, ratings.
- Insulation and lining. The type and thickness where they apply.
- Air terminals. Diffusers, grilles, and registers, with a type and airflow.
- Equipment. Air handlers, fans, and VAV boxes, with identifiers.
- Dimensions. Offsets from grids, walls, and structure so the crew can locate the work.
- Schedules and notes. Equipment, terminal, and damper schedules, plus general notes.
How do you produce an HVAC shop drawing in Revit?
1. Link accurate backgrounds
Design models are often not detailed enough for trade coordination. Link verified architectural and structural models with Insert, Link Revit, and set positioning in Manage Links.
2. Model the duct system and check it
- Model ducts, fittings, accessories, air terminals, and equipment, and connect them.
- Run Check Duct Systems on the Analyze tab, and Show Disconnects.
- Review warnings in Manage, Inquiry, Review Warnings.
- Run clash detection against the structure and other trades.
3. Build the views
- Create a plan for each level, and sections through congested areas.
- Apply a view template that shows the ducts in full and the background in halftone.
- Set the scale and the detail level. A fine detail level shows fitting lines and insulation wraps.
4. Tag the ducts
Size and elevation on every run where they change. The steps and the settings are in the guide to tagging ducts, the duct size tag guide, and the duct elevation tag guide.
5. Tag fittings, accessories, and flex
Tag the fittings that carry information, and every damper, silencer, and access door. See the duct accessory guide and the flex duct guide.
6. Tag air terminals and equipment
Diffusers and grilles carry a type and an airflow. Equipment carries an identifier and a model. See the air terminal guide and the equipment guide.
7. Dimension, schedule, and sheet
- Dimension duct offsets from grids and walls with Annotate, Dimension, Aligned.
- Create schedules for equipment, air terminals, and dampers.
- Place the views and schedules on sheets with your titleblock.
- Run the MEP sheet QA checklist before you issue.
What goes wrong on HVAC shop drawings?
| What you see | What to check |
|---|---|
| A duct has no size | The run was missed by Tag All, or the tag is hidden in the view. |
| Elevations disagree with the coordination model | Check which elevation the tag reads and whether the model changed. |
| Fire dampers lack ratings | The rating is a family parameter, not a shared parameter. |
| Air terminal airflow shows zero | Check that the system is connected, and install the latest Revit update. |
| Tags cover the insulation wrap | Revit does not check overlaps. Move them by hand. |
| Tags are out of date after coordination | Retag the changed runs. |
What else breaks when you draw HVAC shop drawings by hand?
Coordination changes. Routes move for weeks, and the tags stay. RayCAD's Retag tool redoes the tags on whatever you select, with the same settings, and Review Tags lists what it could not place.
RFIs. A missing size or elevation becomes a question from the shop. See how RayCAD reduces RFIs.
How does RayCAD tag an HVAC shop drawing?
You pick the views. RayCAD reads the model, decides where tags belong, places them, and lists anything it could not place. You review the result. With a click-saver, each click is quicker, and you still decide and place each tag.
RayCAD tags rectangular, round, oval, and flex ducts, fittings, accessories, air terminals, and mechanical equipment, native and fabrication, in floor plans and section views. It does not set up views, sheets, or dimensions.
| Task | In Revit by hand | With RayCAD |
|---|---|---|
| Choosing which runs get a tag | You read every run | Tagged where the information changes, by your rules |
| Tagging six categories | Six passes | One run |
| Keeping tags clear of the model | You move them | Each position is checked against the model and other tags |
| Following your standard | You remember it | Your tag families and layouts, applied every time |
| Finding what needs attention | You scan the sheets | A review panel |
What should you check before you issue the sheet?
- Every run has a size, and an elevation where it changes.
- Every damper, silencer, and access door is tagged and rated where required.
- Every terminal and unit matches its schedule.
- The set passes the MEP sheet QA checklist.
RayCAD runs inside Revit 2021 to 2027. Try it free, or email us for a demo and we'll onboard your team. The general workflow is in the guide to MEP shop drawings. Contractors can read RayCAD for MEP contractors.
What building an HVAC tagging script yourself really costs
- Time. Whoever builds and maintains the script is doing software development instead of the billable engineering and drafting work they were hired for.
- The AI loop.With Claude or ChatGPT it becomes an endless loop of “fix this”, “now fix that”. Each fix can break a case that worked before, and nobody on the team owns the code.
- Cost. Hours spent building and maintaining scripts, times your hourly rate, against $200 per month for RayCAD for the whole company.
You can build an HVAC tagging script, and this page shows how. For production MEPF sheets, RayCAD is the cheaper and safer choice. Try it free for 15 days.
Frequently asked questions
What goes on an HVAC shop drawing?
Duct sizes, routing, elevations, fittings, dampers and access doors, insulation and lining, air terminals, equipment, and the dimensions that tie them to the structure.
What is the difference between HVAC working drawings and shop drawings?
Working drawings guide installation from the design. Shop drawings are prepared by the installing trade and show the fabrication and installation detail. The terms overlap in practice, so confirm what your contract requires.
How do I produce HVAC shop drawings in Revit?
Link accurate backgrounds, model the duct system, build plan and section views from view templates, dimension, tag every element, schedule the equipment and terminals, and place the views on sheets.
Which tags does an HVAC shop drawing need?
Duct size and elevation, fitting identifiers, damper marks and fire ratings, air terminal type and airflow, and equipment identifiers.
How long does it take to tag an HVAC shop drawing?
It depends on the size of the floor and your standard. The tagging is usually the largest manual step.
Can RayCAD tag HVAC shop drawings?
Yes. RayCAD tags rectangular, round, oval, and flex ducts, fittings, accessories, air terminals, and mechanical equipment, native and fabrication, in floor plans and section views.
Sources
- Wikipedia, Shop drawing (checked October 21, 2026)
- DEV Community, Mastering HVAC shop drawings (checked October 21, 2026)
- AUGI, The ABCs of MEP construction modeling, part 2 (checked October 21, 2026)
- Autodesk Revit help, Tag All Not Tagged (checked October 21, 2026)