Your Ceiling Is the Dispatch Board, Not the Market
Take a technician you pay for a full 8-hour day. Industry reporting on field-service trades has pegged the billable share of that day at around 65 percent, and a separate operations study found roughly 3 of those paid hours going to something other than optimized, revenue-producing work. Drive time, waiting on a part, hunting a purchase order, writing up the last job, sitting idle because dispatch had a gap. You paid for all 8. You billed for 5.
That gap is your real growth ceiling, and it has nothing to do with demand. Owners feel maxed out and reach for the obvious lever, which is more trucks and more bodies. Sometimes that's right. More often you're paying to add capacity on top of capacity you already own and don't fully use, which is an expensive way to solve a problem you don't actually have.
Utilization is the number, and most shops are guessing at it
Utilization is the share of paid technician hours that lands on a billable invoice. Well-run plumbing shops tend to sit somewhere between 60 and 75 percent, and the operators who study this call 70 to 80 the zone where the economics actually work. The connection to profit is not subtle. To clear a 20-percent net, the rule of thumb floating around the better-run shops is that your techs need to be roughly 80-percent billable. Miss that by 10 or 15 points and the net doesn't shrink a little. It disappears, because the unbilled hours are pure cost with no invoice on the other side.
Here's the part that stings. A shop at 65 percent and a shop at 80 percent can look identical from the street. Same trucks, same brand on the door, same busy techs who will all swear they never stop moving. The difference doesn't show up in how hard anyone works. It shows up in how many of the hours you already bought turned into money, and that number lives on the dispatch board, not on the demand side of the business.
Revenue per technician tells you where you really stand
If you want one figure to manage to, use revenue per technician. Benchmarks for plumbing put a fully productive tech somewhere in the range of $160,000 to $220,000 a year, with emergency-weighted shops running higher because the work carries more urgency and less price shopping. Pull your own number. Take your service revenue, divide by your field techs, and set it against that range.
If you land low, resist the reflex to blame the techs. The hours are usually lost around the work, not during it. Look at the schedule first. Every gap between jobs is paid time producing nothing, and gaps come from routing that zig-zags across the metro, from a dispatcher filling slots by feel, from second calls that could have been prevented on the first visit. Look at the trucks next. A tech who drives back to the shop or the supply house for a common part just converted a billable hour into a mileage expense, and the fix is stocking the truck, not lecturing the man driving it. Look at the handoff last. Time spent writing up work, chasing approvals, and re-explaining a job to the office is time nobody invoices.
None of that requires a bigger team. It requires knowing, this week, what your utilization actually is, so you stop managing to how busy everyone looks and start managing to how many paid hours cleared.
The cheapest truck you'll ever add is the one you already own
Adding a truck adds cost tonight and revenue someday, assuming you can hire and hold the person to run it, which at the moment is its own gamble. Moving your utilization from 65 to 75 pulls revenue out of trucks you already bought, techs you already pay, and demand that's already calling. It is the same growth without the payroll, and it shows up next month instead of next year.
So before you finance the eighth truck, find out what the 7 you have are actually billing. Measure the hours you pay against the hours you invoice, name the 3 biggest leaks, and close them. The demand is not your constraint. The board that decides where those hours go is your constraint, and unlike the market, you own it.