On a civil job the number that goes out can look finished. The sections add. The lump is round. The returnable schedule has a figure in every cell that was supposed to have one.
Then someone asks how you got there — a tender query, a variation against the original allowance, an alternate that was or was not in — and the working is not a thing you can produce. It is a spreadsheet, a marked-up bill, a chat, and whoever still remembers the last pass.
First, the part that looks fine
The submitted form is doing a job. Principals already ask for a price in their shape: lumps, schedules of rates, provisional sums, mandatory alternatives, optional additional work. Public civil suites ship those as tender schedules, so the shape of the return is often set before an estimator opens a spreadsheet.
A tidy return is what gets a bid conforming. It is not what lets anyone defend the build-up six weeks later.
That distinction is worth a moment, because “the price looks right” is easy to confuse with “the price can be explained”. They are different tests. One is arithmetic on the form. The other is a trail — which section, which rate, which allowance, which alternate, which version of the scope.
Then the part that fails
The failure is rarely the calculator. It is the working.
- Sections. A number was built by work section or separable portion, then flattened. When a query lands on this drainage run or that pavement, the section total is gone and the allowance has been absorbed.
- Alternates.An option was priced on a side sheet, or as a mandatory alternative, or as “we will look at that if we win”. Later, ops is living inside one of those worlds and cannot show which one the submitted number assumed.
- Unpriced forms. A rate left blank, a provisional sum never built up, a returnable that never got a number. In the last pass it is easier to bury it in a lump than to leave a hole. The hole is still there; it is just no longer visible.
- What changed. Addenda land. Quantities move. A rate is cut to meet a number. The submitted form shows the last state. It does not show the path.
- Who decided. The estimator cut it, ops accepted the risk, someone said yes on the phone. When that person is on the next tender, the decision left with them.
None of that is a sloppy-estimator story. It is what happens when the record of the estimate is treated as a private worksheet rather than as evidence.
Why “looking right” is the wrong test
A numeric total is, quietly, a gift to the person who only has to submit. It converts an open-ended build-up into one line. Take away the working and that line is all there is.
The moments that test it are ordinary ones:
- a clarification that asks you to stand behind a rate;
- a variation that only makes sense against what was originally allowed;
- a separable portion that has to be valued on its own;
- an alternate the principal now wants to take;
- an internal review after a win, when ops asks what they have actually bought.
“It can be reconstructed if anyone asks” is a weak position in all five. A reconstruction is a story told afterwards, usually by someone who was not in the room, out of whatever happens to have survived.
What we do about it
FieldTaskora is built for the gap between a number that adds up and a number that can still be explained.
- The estimate keeps its structure. Sections, items and alternates stay attached to the figure they belong to, instead of collapsing into a lump that cannot be unpacked.
- Unpriced and incomplete stay visible.A blank rate, a provisional, a form that never got a number is a fact on the estimate — not something the last pass is allowed to hide.
- Changes carry their working. What moved, from what, to what, is part of the record rather than a new file name.
- Decisions have an owner.Who accepted the number — and which number — sits on the estimate, so the trail does not depend on who is still in the room.
- It comes back out as a pack. The same record can be produced when the query, the variation or the internal review arrives, generated from what was captured rather than rebuilt from memory.
The honest summary
Most estimates that look right are right enough to submit. The arithmetic is not the scandal.
The exposure is the one that shows up later: a number that cannot show its sections, its alternates, its unpriced holes, what changed, or who decided. That is an evidence problem wearing a commercial costume.
Worth being able to produce the working before someone asks for it.
On the shape of a priced return: NSW Government’s MW21 tender schedules, and its construction practice guide on alternative tenders, which describes alternatives being priced on a separate schedule. Cited as examples of what a submitted form often looks like, not as duties that apply to every contractor. This is general information about estimating practice, not legal or commercial advice — check the conditions of tender and the contract you are actually under with your own adviser.