Rev C on the wall, Rev E in the inbox
The lighting layout for the second floor has been revised twice since your team printed it. Revision E moved a row of downlights and added a feature pendant. Your electricians have spent two days installing to Revision C. Nobody told them. The office received the email, saved the PDF, and moved on.
Now it's rework, an awkward conversation with the main contractor about who pays, and a site team who don't trust the drawings any more.
The main contractor's document platform did show the new revision. Nobody on your team had logged into it that week, because the office assumed site would, and site assumed the office would.
Why old drawings stay in use
Designers and main contractors issue revisions through email, file shares or document platforms. Your office receives them. Getting them to the right people on site, and making sure the old version disappears, is a manual step that competes with everything else.
Printed drawings are the worst offenders. Once pinned up, they stay until someone takes them down.
| Where drawings live | Risk |
|---|---|
| Office inbox | Received but not passed on |
| Site cabin wall | Printed, never replaced |
| Electricians' phones | Old PDF saved months ago |
| Main contractor's platform | Current, but nobody on your team checks it |
Revisions are not always obvious either. A drawing can change without a big note on it: a revised clouded area, a moved fitting, a new symbol in the legend. The revision letter in the title block is the only reliable clue, and on a crumpled printout in a site cabin that is easy to miss.
What superseded drawings cost
Rework is the obvious cost: time, materials, sometimes making good. Disputes follow about who pays, and your position is weaker if you can't show when you received a revision and when you passed it on. Programmes slip, and main contractors remember which subcontractors caused delays.
It also wastes materials. Fittings bought for the old layout may not suit the new one, containment may need moving, and cable already pulled may be too short. Some of that can be reused, some cannot.
The drawing register we build
- Capture: drawing issue emails and platform notifications are collected, and each drawing is logged with its number, title and revision.
- Change summary: the new revision is compared with the previous one, and the revision notes plus visible differences are summarised for the supervisor to check.
- Current set: the site team opens one link that always shows the current revision of every drawing. Old versions are clearly stamped superseded.
- Site notice: when a drawing in an active area is revised, the supervisor gets a message with the summary and a reminder to replace printed copies.
- Acknowledgement: the supervisor confirms the revision has been briefed, and the date is recorded.
- Record: the register shows when each revision was received and briefed, which matters if a dispute arises later.
Printed copies are still allowed. Each printout carries its revision and the date it was printed, and the supervisor's reminder lists which printed sheets need replacing, so the cabin wall stays current.
One current set for everyone
Your electricians open one place and see the latest drawings. Revisions reach site the day they arrive. And if there's ever an argument about rework, you have a dated record of what you received and when you acted on it.
It also helps with handover. When the job finishes, your as-installed record can be marked up against the final revision, because you know exactly which revision each area was built to.
Supervisors also spend less time double-checking. Instead of ringing the office before starting each area to ask whether anything has changed, they can open the register and see.
Recognise this?
- Rework has happened because site used an old revision.
- Revisions arrive by email and aren't passed on straight away.
- Printed drawings stay on site walls long after they're replaced.
- You can't show when a revision was received and briefed.
- Electricians keep their own copies of drawings on their phones.