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AI drafting for background updates

AI Drafting for Architectural Background Updates

Every time the architect reissues backgrounds, each consultant has to find what moved and redraw around it, usually by flipping between two xrefs and squinting at the overlay. Nomic compares the two revisions, lists the walls, doors, and ceilings that changed, moves the affected devices, ducts, and framing on your sheets, and clouds each edit so your engineer reviews only the delta.

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Last reviewed: November 2026

You send

  • The new architectural backgrounds as DWG or PDF
  • The previous background revision your sheets are drawn on
  • Your current consultant DWGs and CAD standards
  • The architect's narrative or transmittal, if there is one

Nomic hands back

  • A change list between the two background revisions, by room and sheet
  • Updated consultant DWGs with every edit clouded and tagged
  • Plotted PDFs of the affected sheets for review
  • Open questions where a move needs an engineering decision
1234567ABCCLASSROOM201CLASSROOM202CLASSROOM203CLASSROOM204CLASSROOM205CLASSROOM206CLASSROOM207CLASSROOM208CLASSROOM209CLASSROOM210CLASSROOM211CLASSROOM212MEDIA CENTER213STAIRS224x14AHU-127'-3"27'-0"27'-3"27'-3"27'-0"27'-3"94'-8"1AHVAC PLANSCALE: 1/8" = 1'-0"N1234CONSULTING ENGINEERSREVISIONS1ISSUED FOR REVIEWPROJECTMAPLE RIDGE SCHOOLSCALE1/8" = 1'-0"DATE01/12/2026KEY PLANSHEET TITLEHVAC PLANSHEET NUMBERM-101

On the sheet

HVAC Plan, annotated

A mechanical plan with supply and return ductwork, diffusers, and the equipment that serves each zone.

  1. 1Main supply duct, sized width by depth
  2. 2VAV box feeding the zone
  3. 3Supply diffuser at the end of the branch
  4. 4Return grille

The problem

Backgrounds change more than the transmittal says

A background transmittal rarely says everything that changed. A corridor wall slides 8 inches, a door swing flips, a soffit drops to 8'-6", and none of it is clouded on the architectural sheets because the architect is mid-design. The consultant drafter reloads the xref, sees nothing break, and the receptacle that now sits inside a wall or the diffuser that now lands on a soffit edge survives until the coordination meeting or the field.

Finding the changes means overlaying Rev 4 on Rev 5 in a contrasting color and scanning sheet by sheet. Fixing them is the same small edit repeated across power, lighting, mechanical, plumbing, and framing plans, and on a project that reissues backgrounds every two weeks during design development, that cycle eats most of the drafting budget between milestones.

01 / Compare

Every change between two background revisions, listed

Attach the new architectural backgrounds alongside the set you are drawn on. Nomic compares the two revisions entity by entity and room by room, then lists each moved wall, resized opening, renumbered room, and ceiling height change with the consultant sheets each one touches.

  • Moved and added walls, flipped door swings, and new openings
  • Ceiling height, soffit, and bulkhead changes from the RCP
  • Room names and numbers that no longer match your tags
02 / Update

The affected layouts move with the walls

Nomic edits your consultant DWGs to match the new backgrounds: receptacles slide with the wall they were on, a diffuser shifts off the new soffit, a header gets redrawn where a door opening widened. Every edit is clouded and tagged with the revision delta, and the unaffected areas of the sheet are left alone.

  • Devices, fixtures, and diffusers relocated to the new walls and ceilings
  • Circuiting, duct runs, and framing redrawn where a move breaks them
  • Room tags and keynotes updated to the new room numbers
03 / Check

Checked for what the move broke

A moved wall can quietly break a code clearance or a coordination condition that was fine on the old background. Nomic rechecks the updated areas against the code edition you name and lists anything that needs an engineering decision, such as a panel that lost working space or a sprinkler that now sits too close to a new soffit.

  • Working space at panels and equipment rechecked against the new walls
  • Device spacing rules rechecked where walls lengthened or split
  • Conflicts the redraw cannot resolve listed for the engineer

Checked against

The code and documents behind every sheet

Name the editions the project is designed to and Nomic checks its own drawing against them before handing it back. Your engineer or architect of record makes the final call and stamps the set.

  • The previous and current architectural background revisions
  • NEC (NFPA 70) working space and receptacle spacing
  • NFPA 13 sprinkler obstruction and deflector rules
  • International Mechanical Code clearances
  • Your firm CAD standards for clouds and revision tags

How it works

From a sentence to a stamped set

  1. Step 1

    Ask for the drawing

    Say what the sheet needs to show and attach the backgrounds, markups, cutsheets, or photos. A sentence is enough to start.

  2. Step 2

    Nomic drafts it in CAD

    Nomic works in CAD on its own computer, on your layers and blocks, following how your firm drew the same thing before. It saves real DWG files to the project.

  3. Step 3

    Nomic checks its own work

    The drawing is checked against the code editions you name and the source documents. Everything Nomic drew is clouded, and open questions are listed.

  4. Step 4

    Your team reviews and stamps

    Your engineers and architects review the clouded changes, make the final call, and issue the set under their own stamp.

FAQ

Frequently asked questions

Most consultant teams reload the new background xref, overlay it on the old revision in a contrasting color, and scan each sheet for walls, doors, and ceilings that moved. Then a drafter edits every affected device, duct, or framing member and clouds the change. Nomic does the comparison and the edits and leaves the review to your engineer.

Yes. Nomic compares the two background revisions directly instead of relying on the architect's clouds or narrative, so a wall that moved without a cloud still shows up in the change list. Changes Nomic cannot pin down, such as a scanned PDF background that is too coarse to measure, are listed as open questions.

No. The architectural backgrounds stay as the architect issued them. Nomic reads them and edits only your consultant DWGs, so the xref relationship in your set stays the same.

The engineer of record. If a moved wall takes working space from a panel or puts a duct main through a new shaft wall, Nomic flags the conflict and can draft the options your engineer describes, but the final call on the design stays with the engineer.

No. Nomic works in CAD on its own computer and saves DWG files you open in AutoCAD or any DWG editor. Teams that model in Revit get DWGs and a change list a modeler can carry into the model.

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AI Architectural Background Updates for MEP Sheets | Nomic