As-built records: keeping them current during the job
At 16:30 on a Friday, the plumbing foreman mentions that he moved the sanitary main under the slab 600 mm north to clear a new grade beam. Everyone nods and heads home. Nobody marks the drawings. Two years later, the owner's contractor cuts the slab for a floor drain where the record set shows nothing, and hits the pipe.
As-built records go wrong because the change happens in the field and the drawing lives in the office. A foreman moves a line, an RFI answer arrives as a sketch, an excavator finds an uncharted pipe, and each fact stays in someone's head until the end of the job, when nobody remembers the dimension. Some owners write the fix into the contract: one US federal guide specification calls for the working as-built markups to be kept current weekly, with a set on site at all times, and submitted for approval before each monthly payment request. It lets the owner withhold part of the payment until updated drawings are approved.
- Keep one master set on site and name the person who owns it. Trades mark their own copies; the master is updated from them.
- Mark each change the day it happens, in a colour that stands out, with a dimension to something that will still be there: a gridline, a wall face, the finished floor.
- Write the reason beside it: the RFI, change order, site instruction or field decision.
- Record what the ground and the walls will hide: buried services by location, size and depth with offsets to permanent features, and anything unexpected found while digging.
- Photograph before cover with a tape in the frame, and note the photo numbers on the markup — see documenting concealed work.
- Check the set at the weekly coordination meeting: each trade confirms its changes are on the master.
- Review the markups before every progress claim, so gaps are found each month, not at handover.
Common mistakes
- Drawing the as-builts from memory in the last week of the job.
- Markups with no dimension ("moved east") or no reason.
- Trade copies that never reach the master set.
- Recording design changes but not field deviations, which nobody else knows about.
Action list
Start this week
- Name the owner of the master set
- Keep the set where foremen pass it every day
- Dimension every change to a fixed reference
- Write the RFI or change number beside it
- Photograph buried and concealed work before cover
- Check the markups at the weekly coordination meeting
Check your understanding
A foreman shows you a reroute marked on his own drawing but not on the master set. Why does that matter if the change is recorded somewhere?
