No house is built from the first drawing. It is built from the fifteenth — after the kitchen grew, the corridor widened, the third bedroom traded places with the study. The design work happens in revisions, and so do the disputes. A revision history is the difference between a project that can answer questions and one that can only argue.
What a revision actually is
A revision is a named, dated, describable change. Not “the new plan”, not final_FINAL_v2.dwg, but a record that reads like a draftsperson wrote it: rev-007 · widened main corridor to 1.2 m, shifted master bedroom east 400 mm. Verb, dimension, direction. One line, specific enough that anyone can find the change on the drawing without asking.
Why memory is not a record
A residential project runs for months and passes through at least four pairs of hands — client, architect, county approvals, contractor — with decisions scattered across site visits, phone calls and WhatsApp threads. Everyone remembers agreeing; nobody remembers agreeing to the same thing. The most expensive sentence in construction is “I thought we had agreed”, and it is always said standing next to concrete that has already set.
What a good record contains
- An identifier — rev-001, rev-002, in unbroken sequence. Gaps invite doubt.
- A date — when the change was made, not when someone got around to noting it.
- A one-line diff — what changed, with numbers: which wall, how far, which direction.
- Who asked and who approved — the client requested; the architect drew and signed.
- What it supersedes — so there is never a question about which sheet is current.
The approval is the point
The record exists so that approval means something. When a client signs off, they sign off on a revision, not on “the plan” — and the county approves a specific drawing set, not a folder of good intentions. If a wall moves after approval, the history shows when it moved, who asked, and who agreed. That protects the client from silent changes and protects the architect from remembered ones. It is the professional record on which the architect of record stakes their name.
On site, it is the referee
The classic building-site failure: the contractor prices rev-005, the client walks the slab with rev-007 folded in a pocket, and the fundi is working from a photocopy of something older than both. This is why proper sheets carry the revision id in the title block — the small rev-007 in the corner is how you check, in seconds, that everyone on site is building the same house. Any sheet without one is a rumour.
Keeping one without special software
Discipline beats tooling. A single page at the front of the project file: id, date, one-line diff, initials of who asked and who approved. Never reuse a filename; never issue a drawing without bumping the number; never accept “small change, no need to log it” — the small ones are precisely the ones that get argued about, because nobody thought them worth writing down.
How Chimbuko does it
In Chimbuko the record keeps itself. Every change — yours by chat, or drawn on the canvas — is stamped automatically as a revision with the one-line diff written in drafting language, every revision is reversible, and the exported sheets carry the revision id in the title block. Approvals are recorded against the revision they approved, so “we approved revision B on the 14th” is not a recollection — it is a sentence the workspace can prove.
See the revision loop in the product, or look at a sample sheet — the rev id is in the title block, where it belongs.