How Does an Architect Issue a Drawing Revision?

A revised sheet always travels inside something. During construction it is usually an ASI, the architect's instruction for a minor change, or a bulletin, a package of changes the contractor is asked to price. Before bids it is an addendum. The vehicle says what the change means for the contract; the sheet shows the change itself. ASI vs RFI explains the difference between the instruction and the question that often starts it.

The marks are a drafting convention rather than a single law. The U.S. National CAD Standard (NCS version 7, from the National Institute of Building Sciences) is the common reference; it includes the Uniform Drawing System and the AIA CAD Layer Guidelines, it is licensed rather than free, and many offices write their revision rules into their own CAD manual. Public agencies publish theirs, and the two below show the choices you have to make.

Many building-design offices follow the left column: cloud and delta every change, strike through rather than erase where the old information matters, and clear the old clouds at each new issue while keeping each delta and the revision block history.

1. Make the change on every sheet it touches: plan, sections, details, schedules. One moved door is often a floor plan, an enlarged plan, a door schedule and an electrical plan.
2. Remove the clouds from the previous revision on each sheet you reissue. Leave the old deltas, so the sheet's history stays readable.
3. Cloud each changed area, tightly enough that a reader finds the change without searching.
4. Place a delta with the new revision number beside each cloud.
5. Add a line to the revision block: number, date, and a description that names the vehicle ("Bulletin 2: add floor box at conference 110").
6. Update the sheet index on the cover sheet so it lists the current revision of every sheet.
7. Issue the sheets together under the ASI or bulletin with a transmittal: each sheet number, title and revision.

A fictional office fit-out, Harbor Point Offices, floor 2. The tenant wants power and data at the conference table in room 110, so the architect issues Bulletin 2 and asks the contractor to price a floor box. A minor change with no price would go out as an ASI instead; see how to write an ASI.

The revision numbers differ by sheet, which is normal where each sheet counts its own issues. The transmittal ties them to one event. Where the federal clause applies, FAR 52.236-21 has the Contracting Officer "furnish from time to time such detailed drawings and other information as considered necessary, unless otherwise provided", and the contractor keeps "a copy of the drawings and specifications" on site; a clean set of current sheets is what makes that copy right.

• Changing a sheet without a cloud. The field doesn't reread a whole sheet; an unclouded change gets built wrong.
• Leaving every old cloud on. After three revisions the sheet is all clouds and nobody can see this week's change.
• Revising one sheet of several. The plan says one thing and the schedule another; the specification governs on federal work (FAR 52.236-21 says "the specifications shall govern" in a conflict between drawings and specifications), but two sheets that disagree start an RFI.
• A revision block that says "revised per comments". Name the ASI, bulletin or RFI.
• Burying a cost change in a revision. If it changes scope, say so and route it as a change.

In Conflo's drawings, the GC or the design team issues a set, such as Bulletin 2, with an issue date and a note on what changed. Each sheet number that already exists gets its next revision and the previous one is marked superseded, never deleted. The log shows the current set by default; opening an old revision warns not to build from it and links to the current one. Each sheet shows its revision history and the RFIs that reference it.

Conflo numbers revisions by its own count of issues for that sheet, starting at Rev 0, so it may not match the delta on a sheet whose earlier revisions were issued before the project moved to Conflo. The clouds and deltas stay on the sheet itself.

A drawing revision is readable when every change has a cloud and a delta, the revision block names why, and only this issue's clouds are on the sheet.

Issue revised sheets together under one ASI or bulletin with a transmittal, so the contractor can retire the old sheets the same day. Architects can read the CA guide for the rest of the phase, and the project lifecycle for the whole job.

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1. Creating Plan Revisions, B.S.B. Version (MicroStation CONNECT Edition), November 2024 — Iowa Department of Transportation, Bridges and Structures Bureau. Read October 22, 2026.
2. Plans Preparation Manual M 22-31.13 (September 2025), Appendix 5, Addendum Preparation — Washington State Department of Transportation. Read October 22, 2026.
3. United States National CAD Standard, Version 7 — National Institute of Building Sciences. Read October 22, 2026.
4. FAR 52.236-21, Specifications and Drawings for Construction — Acquisition.gov (General Services Administration). Read October 22, 2026.