Nine Trips To The Job, Two Of Them Billable
Your crew makes nine separate trips to that building, from underslab to punch. The schedule of values has one line on it that says rough-in.
A drywall crew comes in, hangs, finishes, and leaves. Mechanical work is embedded in every phase from the slab to the ceiling grid, so the schedule keeps calling you back, and your equipment doubles as the building's temporary heat while other trades finish. Both the return trips and the temp use are costs created by the schedule, and neither one has an SOV line waiting for it.
The size of it
You eat four to six unbudgeted mobilizations at $3K to $6K each on a mid-size job, plus temp-use wear nobody wrote a change order for. That's $25K to $40K of cost with no billing line attached to it.
The trips run underslab, deck sleeves and hangers, overhead rough-in, roof curbs before the roofer dries in, unit sets on a crane day the GC picks, ceiling trim after the drywall, start-up, TAB, and punch. That's eight or nine discrete visits, each with its own travel, lift rental, and foreman ramp-up time, and the schedule of values bills by system percentage, so remobilization cost never touches a billing line. Then the GC asks to run the permanent equipment for temporary heat during drywall, and you absorb construction filters, coil cleaning, and belt wear on units nobody has accepted. The warranty clock on that equipment starts running months before the owner takes the building.
Three moves, in order
Step 06: Project management
Billing dates, change orders, and notices, run as standards that hold without anyone chasing them.
What else costs mechanical contractors money
The same mechanism in other trades
What mechanical owners ask
How to bill for multiple mobilizations on a mechanical job?
Your crew makes nine separate trips to that building, from underslab to punch. The schedule of values has one line on it that says rough-in.
What does it cost?
You eat four to six unbudgeted mobilizations at $3K to $6K each on a mid-size job, plus temp-use wear nobody wrote a change order for. That's $25K to $40K of cost with no billing line attached to it.
What do I do first?
Write the full mobilization list into the SOV at buyout and put a dollar value on each one: underslab, sleeves and hangers, overhead rough, roof curbs, unit sets, trim, start-up, TAB, and punch.
What are mechanical contractors supposed to be making?
Mechanical runs 25% gross margin, 16% overhead and 9% net profit before taxes at $1M–$5M. The all-trade average is 7%, so this trade sits 2 points above it. The CFOS target is 11%.
Which part of the system fixes it?
The step is number 06, project management. Billing dates, change orders, and notices, run as standards that hold without anyone chasing them. It comes from chapter 6 of CONTROL: The Construction Financial Operating System.
Josh Luebker ran commercial construction projects before he ran the numbers behind them, on data centres, military bases, hospitals, and high-rises. He wrote CONTROL: The Construction Financial Operating System, which is an eight-step framework for commercial subcontractors, and it publishes on October 1, 2026. He is a master electrician who moved into the office and kept the field vocabulary.
Sulphur Prairie Operations LLC maintains the benchmark reference behind these figures. Every edition is reconciled against the newest CFMA survey release before it publishes here. Where a figure changes between editions, the older edition keeps its year in the title so a citation to it stays correct.