Ask an owner what their technicians did yesterday and you will get a confident answer: six jobs, all completed, no callbacks. Ask how many hours those technicians spent driving and the answer gets vague. Somewhere between two and four? Depends on the day.
That vagueness is not sloppiness. It is structural. In most field service businesses, drive time is not a line item anywhere. It hides inside the appointment. A job blocked out from 9:00 to 11:00 might be forty minutes of driving and eighty minutes of work, and the schedule records it as one two-hour job. The report says the truck was busy. It does not say what the truck was busy doing.
Windshield time is the share of a paid day your crews spend behind the wheel instead of in front of the work. It is the single largest cost most field service companies have never measured.
Why the number stays hidden
There are three reasons drive time is so hard to see, and all three are worth naming because each suggests a different fix.
It is booked as work. When a dispatcher blocks two hours for a service call, that block covers travel, setup, the job, and cleanup. Nothing in the calendar distinguishes them. At the end of the week, utilization reporting reads that block as two hours of assigned capacity.
It is absorbed by padding. When a scheduler is not sure how long the drive will take, the safe move is to leave room. Add thirty minutes. Give the customer a wider window. That padding is real time on a real truck, and it is invisible because nothing was ever promised in it.
It is variable in a way averages destroy. A twelve-mile drive at 7:00 a.m. and the same twelve miles at 4:30 p.m. are different jobs. Most scheduling systems store one distance per pair of addresses, so the difference disappears into a mean that is wrong at both ends of the day.
Both columns describe the same technician on the same day. One of them is on your utilization report. The other is on your payroll.
What it costs, in numbers you can run yourself
Skip the industry benchmarks. Your own arithmetic is more persuasive and takes about five minutes.
Take one technician's fully loaded hourly cost — wage, burden, vehicle, fuel, insurance. Call it C. Take the hours per week that technician spends driving. Call it D. The annual cost of that travel is roughly:
C × D × 48 weeks
For a crew of eight, multiply by eight. The number tends to land somewhere that makes people quiet.
But the cost that matters more is not the wage you paid. It is the job you could not take. If a technician spends three hours a day driving and your average job is ninety minutes of work, then roughly two jobs of capacity per technician per day are sitting in traffic. Whether you could actually sell those two jobs is a separate question — but you cannot sell capacity you do not know you have.
A caution on benchmarks. You will find plenty of published figures for "average technician drive time." Treat them carefully. A dense urban plumbing operation and a rural HVAC company with a ninety-mile service radius have almost nothing in common, and an average across both describes neither. Measure yours.
The three levers that actually move it
Once you can see the number, there are only three things you can do about it. They are not equally effective, and most companies start with the weakest one.
Lever 1: Drive less between the jobs you already have
This is route optimization, and it is the lever everyone reaches for first. Given a fixed set of jobs assigned to a fixed truck on a fixed day, find the least-driving order to do them in.
It works. It is also the smallest lever, because by the time you are optimizing, the damage is done. If your 8:00 a.m. is downtown and your 10:00 a.m. is forty minutes north and your 11:30 is back downtown, no ordering algorithm saves you. The sequence was determined when those three appointments were promised to three customers on three separate phone calls, none of which knew about the others.
Lever 2: Assign the job to the truck that is already near it
Better. Instead of asking "which technician is free at two," ask "which qualified technician will be closest to this address at two." Those are different questions with different answers, and the second one is the one that reduces driving.
The catch is that "closest" is not a property of a technician. It is a property of a technician at a specific hour, which depends entirely on what else is on their day. A truck that is nearest to this address at 7:00 a.m. may be the worst possible choice at 3:00 p.m. Answering this properly means computing travel from where the truck will actually be when the job starts — not from the shop, and not from the technician's home address.
Lever 3: Never offer a time the drive makes impossible
This is the largest lever and the least used, because it operates one step earlier than the other two — at the moment of booking, not the moment of dispatch.
Most scheduling tools answer one question when a customer asks for two o'clock: is that block empty? An empty block and a reachable job are not the same fact, and only one of them survives contact with traffic. If the slot gets sold and the drive does not fit, someone absorbs the difference: the technician runs late, the next customer waits, or the dispatcher quietly pads the rest of the day to make room.
Building travel time into availability means the calculation happens before the promise, not after. The slot is only offered if a qualified crew can physically get there in time, given everything else already on their day. Nothing to optimize later, because nothing infeasible was ever booked.
How to start measuring this week
You do not need new software to get the first number. You need timestamps.
- Capture arrival and departure per job, not just "completed." Most field apps already record this; most reports never surface it. If yours does not, a week of manual logging on three trucks is enough to see the shape.
- Compute the gaps. The time between one job's departure and the next job's arrival is travel plus slack. That total is what you are paying for.
- Split travel from slack. Compare each gap to a realistic drive estimate for that pair of addresses at that time of day. The excess is idle — and idle is a different problem with a different fix.
- Break it down by day of week and time of day. Drive time is not uniform. Most companies find one or two structural offenders: a standing Tuesday commitment across town, a recurring account at the edge of the territory.
- Look at backtracking specifically. Count the days where a truck crossed its own path. That is the number that tells you whether your problem is routing or booking.
If the gaps are mostly reasonable drives in a sensible order, your booking process is fine and you have a dispatch problem. If the gaps show trucks crossing the same territory twice before lunch, the driving was created at the moment those jobs were promised, and no amount of dispatch heroics will fix it after the fact.
What to take away
- Drive time is invisible in most field service reporting because it is booked as part of the job and absorbed by padding.
- Measure it from job-level arrival and departure timestamps, then separate real travel from slack.
- Route optimization is the smallest of the three levers — it improves an order that was already set when the jobs were booked.
- The largest lever is refusing to offer times that the drive makes impossible in the first place.
- Backtracking is the diagnostic: trucks crossing their own path means the problem is in booking, not dispatch.
The uncomfortable part
Reducing windshield time usually means telling a customer no. Not a hard no — a "we can do Tuesday morning or Thursday afternoon" no. Companies that book whatever the customer asks for and sort it out later will always have more driving than companies that offer a narrower, feasible set of times.
That trade feels like it costs you bookings. Sometimes it does. What it buys is a day that holds together, crews that finish when they said they would, and capacity you can actually sell — because you know it is real.
Common questions
What is windshield time?
Windshield time is the portion of a field technician's paid day spent driving between jobs, to suppliers, or to and from the shop. It is productive-hours cost with no billable output attached to it.
How do you calculate windshield time?
Take total paid hours for a technician over a period, subtract on-site wrench time and any paid non-driving activity (shop time, training, breaks), and what remains is drive. The cleanest method is to pull start and finish timestamps per job and treat the gaps between them as travel plus slack, then separate the two.
Is some windshield time unavoidable?
Yes. Residential field service means going to the customer, so travel is part of the product, not waste to be eliminated. The goal is to stop paying for avoidable travel: backtracking, crossing your own territory twice, and driving created by the order jobs were booked in.