The one record that wins a quantity dispute
On unit-price work you are paid on what you actually put in the ground. The engineer's count is only final until better data shows up. Here is what better data looks like.
Every unit-price contract says roughly the same two things about quantities, and most contractors have read neither. First: the quantities in the bid schedule are estimates, not guarantees, and you will be paid on actual quantities. Second: the engineer determines the actual quantities, and that determination is final and binding.
People stop reading at "final and binding." They should keep going, because the next clause is the one that matters. The engineer's number stands except as modified to reflect changed factual conditions or more accurate data. And in the standard conditions, the engineer has to review preliminary determinations with the contractor before writing anything down as final.
So the contract hands you two tools. One is procedural: if the engineer cut your pipe footage without walking it with you first, that is a step they skipped, and you say so in writing. The other is the one this article is about. "More accurate data" is a door, and the daily quantity register is what walks through it.
Why the engineer's count loses to a good register
The inspector is on your job part of the day. Your foreman is on it all of the day. The inspector writes a daily report that says something like "crew installed water main, Craig Road." Your register says 212 feet of 8-inch from station 14+50 to 16+62, four fittings, bedding full length, measured by the foreman at 3:40 with the inspector present. One of those is data. The other is a diary.
When the pay estimate comes back short, the argument is never about who is more honest. It is about who has the better record. Build the better record every day and most quantity disputes never become disputes. They become a five-minute phone call.
What the register has to contain
We have built these for our own jobs and rebuilt other people's after the fact, which is far more painful. The working version has, per day, per pay item:
- The pay item number and the quantity in the contract's unit. Not "pipe." The item number from the bid schedule and the unit the schedule pays in.
- Station to station. Linear items get a from and a to. Area and volume items get a location you could find again. "Craig Road" is not a location.
- Who measured it, and who saw it measured. If the inspector was there, say so. If they signed the tailgate sheet, scan it that night.
- Conditional and ordered items, with the order. Rock removal, extra stone, flowable fill: these typically pay only "as ordered by the project representative." The order has to exist before the work does. Write down who gave it, when, and how. A verbal order from the inspector at 7am is worth recording at 7:05am, before anybody forgets they gave it.
- Photos with a tape in them. Phone photos are free. A photo of the trench with the pipe exposed and the tape on the station stake settles more than a page of notes.
Keep it in one place, in order, every day, including the days you installed nothing. A register with gaps gets read as a register someone filled in later.
Two traps that make most registers worthless
The units column. Never trust the unit someone typed into a spreadsheet. On a recent job the bedding item paid by the linear foot, not the cubic yard, and was its own line, not rolled into the pipe. A register that tracked bedding in yards was tracking something the contract does not pay for. Before the first day of work, go item by item through the bid schedule and the measurement-and-payment section, and set the register's units from there. Then do not let anyone "simplify" them.
Related items that should move together and don't. On that same job, bedding footage equals pipe footage, every day, by definition. A register that shows 300 feet of pipe and 180 feet of bedding on the same day is not showing a short bedding run. It is showing that somebody missed an entry, and an inspector will notice before you do. Build the obvious cross-checks into the sheet so a mismatch flags itself the day it happens.
When the unit price itself can change
One more clause worth knowing. Most of these contracts let either side ask for a unit price adjustment when an item is a large share of the contract, the actual quantity ends up far off the estimate, and your real unit cost changed as a result. The thresholds vary. On the job we read, the general specification said one percentage and the supplementary conditions said a tighter one, and the supplementary conditions win. If an item is running well over or under the bid quantity, go find the exact numbers in your own documents before anyone else quotes them to you.
The point
A quantity dispute is a records dispute. The contract already says you are paid on actual quantities and that better data reopens the count. The daily register is the better data. It costs a foreman ten minutes at the end of the day and it is the difference between arguing from memory and handing someone a page they cannot argue with.
This is one of the first things we set up for a contractor, and it is one of the first things we built into our own software, because we needed it before anyone else did.
Short on a pay estimate?
Tell us the item and the job. We will tell you straight whether your records can carry it.