Journal
How to read an S-curve when the brickwork gang is two weeks late
On a recent Highland housing phase, the contractor’s S-curve still looked healthy in month five because groundworks and drainage had been pulled forward. Brickwork, which actually sat on the client’s critical path for first occupations, was barely moving. Anyone reading only the single curve would have signed off a reassuring story.
Before you trust the shape of the line, ask which bill items are inside it. If the curve mixes enabling works with superstructure, a busy earthworks month will hide a quiet brick month. We split the curve by trade package when the accepted programme already names those packages. If it does not, we say so on the face of the sheet rather than inventing a split.
The second question is the baseline. An S-curve plotted against last week’s update is a moving target. Plot it against the accepted programme, then show a second line for the last agreed revision if one exists. Two lines are harder to draw; they stop a late brick gang disappearing into a ‘revised forecast’.
Photographs belong beside the curve, not in an appendix nobody opens. One elevation, dated, with the activity ID in the caption, is enough to test whether the percentage on the curve matches what a visitor would see from the hoarding.
If the curve and the elevation disagree, the pack should say so in a sentence. That sentence is more useful in a client meeting than a smoother line.