Materials stop walking off your jobsites when every item that leaves your shop, van, or gang box is logged out to a job and a person — in seconds, at the moment it moves. Shrinkage survives in the gap where nobody can say what was supposed to be there. Close that gap and you close most of the leak, because the majority of what contractors call shrinkage was never stolen at all — it was used, unlogged, and never billed.
That claim annoys people the first time they hear it, so let’s take the three leaks one at a time — including the two that padlocks and cameras genuinely can’t help with.
“Shrinkage” is three different leaks
Outside theft is the one everyone pictures: the fence materials staged at the curb that are half gone by Monday, the van window at 6 a.m., the copper that left a commercial site in a weekend. It’s real, it’s maddening, and it’s the leak owners spend the most money fighting — because it’s the only one that feels like a crime.
The inside leak is quieter: an open parts cage, helpers grabbing fittings for a side job, stock that migrates into personal trucks a handful at a time. Nobody plans it. It happens because nothing says it can’t — there’s no moment where anyone has to put their name next to what they took.
The quiet leak is the one that costs most shops the most: material your crew used on legitimate work that nobody wrote down. It never hits a job cost, never lands on a bid, and never looks like theft because it isn’t. Run the napkin math: three crews each walking out with $25 of unlogged material a day, 260 working days, is $19,500 a year — leaking in fistfuls of fittings and fasteners, invisible until tax time says otherwise.
Why cameras and padlocks disappoint
Contractors who’ve been hit by outside theft describe the same two discoveries. First, the camera mostly produces evidence, not materials — footage of the theft, a police report, and nothing back. Second, and worse: after a van break-in, the hardest question isn’t who did it — it’s what was even in there. Owners end up reconstructing the contents of a van from memory for the insurance claim, hundreds of dollars in drill bits and fittings at a time, because no list existed.
Locks and cameras fight strangers. But two of your three leaks aren’t strangers — they’re ambiguity. No lock fixes “nobody can say what was supposed to be here.” Accountability does.
What actually stops it: named accountability
- Everything leaves through a checkout. Who took it, which job, how many — captured at the moment material moves, in seconds, on the phone already in their pocket. This is the whole system; everything else supports it. The bar is brutal: logging has to be faster than not logging, or the crew stops within a month and you’re back to fiction.
- Counts have owners and minimums. Label the bins that matter — your top movers, not everything — each with a minimum quantity on the label. A ten-minute weekly walk against those minimums catches drift while it’s still small, and builds the restock list as a side effect.
- The record can’t be quietly edited. An append-only history changes the conversation. “Who took the last three boxes of ProMar?” stops being an accusation and becomes a lookup. Most inside leak dries up right here — not because anyone got caught, but because the ambiguity it needed is gone.
- The purchase side closes the loop. A PO number per job at the supply-house counter means store runs get attributed the same way shelf stock does. We’ve written up that whole system in the material-costs-per-job guide.
The insurance reality nobody warns you about
When outside theft does hit, owners routinely discover their general liability policy doesn’t cover their own materials — that protection usually lives in builders risk or inland marine coverage many small shops never bought. Whatever your coverage, every claim runs on the same fuel: documentation of what existed. A current item list with quantities and locations is exactly what an adjuster asks for, and exactly what a checkout system produces as a by-product. Ask your agent what your policies actually cover — before the morning you need to know.
Roll it out in an afternoon
- List your top 50 movers. Not the whole catalog — the wire, fittings, fasteners, and consumables that actually walk. Label their bins with name and minimum.
- Stage the checkout habit. Whatever tool you use — app, clipboard, whiteboard — the rule is the same: nothing leaves without a name, a job, and a quantity. Announce it as job costing, not policing: “we’re finding out what jobs really cost us.”
- Walk the bins weekly. Ten minutes against the minimums. Anything below min goes on the restock list on the spot.
- Watch the first month of numbers. The first honest month usually surprises owners twice — how much material actually moves, and which jobs eat it. That second surprise is your bidding model correcting itself; see how to know if your estimates are accurate.
InTrack is the checkout habit, minus the friction.
InTrack puts the checkout on every crew phone: scan the item, tap the job, done — seconds per item, tied to a person, on a history nobody can quietly edit. Owners see what left, for which job, as it happens, and job budgets update in real time. Pricing is flat, not per seat — from $99/month for the whole crew — because a tracking system only works when everyone who touches material is on it. The 14-day free trial is the full Pro product, no card required, with a one-click extension to 30 days if you want longer.
Related reading: how to run the whole flow from warehouse to jobsite, and the practical guide to jobsite inventory management if you’re starting from zero.
Common questions
What counts as material shrinkage on a jobsite?
Three leaks: outside theft (materials taken from the site, the curb, or a broken-into van), the inside leak (stock that drifts out of an open parts cage into side work), and the quiet leak — material your own crew legitimately used but nobody logged, so it never lands on a job or a bid. For most small trade shops the quiet leak is the biggest of the three by dollars, and it’s the one cameras and padlocks can’t touch.
Do jobsite cameras stop material theft?
Cameras deter some outside theft and help police reports, but contractors who’ve been hit describe ending up with good footage and no materials. Cameras record; they don’t create accountability. They also do nothing about the two bigger leaks — inside drift and unlogged use — because those aren’t break-ins. A checkout system that names who took what, for which job, closes the gap cameras leave.
How do I stop my own crew from taking materials?
Accountability without accusation. When every item leaves through a quick checkout tied to a job and a person, casual taking mostly stops on its own — not because anyone got caught, but because the ambiguity it depended on is gone. The rule that makes crews actually do it: the checkout has to be faster than not doing it. Seconds per item, from the phone already in their pocket, or the system dies in week two.
Does insurance cover materials stolen from a jobsite?
Often not the way owners expect. General liability typically doesn’t cover your own materials; coverage for materials and equipment usually lives in builders risk or inland marine policies, which many small shops don’t carry. And any claim depends on documenting what existed — a current item list with quantities and locations is exactly the evidence an adjuster asks for. Talk to your agent about what your policies actually cover before you need the answer.