If you run a contracting business and your P&L looks profitable but your bank account never quite reflects it, the problem almost certainly lives at the job level. Company-wide gross margin is a summary; it tells you the outcome but not the cause. Job costing tells you the cause — and for most established contractors, the cause is a handful of repeating leaks that are entirely fixable once you can see them.
This is not a primer on setting up QuickBooks job codes. This is about the structural places margin disappears, why standard bookkeeping won’t catch them, and what a tighter costing discipline actually looks like in practice.
Why Does Your Overall Margin Keep Shrinking Even When Individual Bids Look Right?
The bid looked like a 28% gross margin job. The final job report — if you ran one — showed 14%. That gap is not bad luck. It is almost always the compounding of several small, predictable failures: labor that ran over because burden was underestimated, materials that shifted but the change order never got signed, and costs that hit the books in the wrong period.
Each failure is survivable once. All three on the same job, repeated across your backlog, compounds into a business that is working hard for a fraction of what it should be earning.
What Is Labor Burden, and Why Do Most Contractors Undercost It?
Direct labor on a job is not the wage you pay. It is the wage plus every cost your business incurs to have that employee on-site: payroll taxes, workers’ comp, general liability (job-site allocation), health insurance, tool allowances, paid time off, and any profit-sharing or retirement contribution. For a field laborer paid $28 per hour, the fully-burdened cost often runs $38 to $46 per hour — sometimes higher depending on trade and risk classification.
Most contractors who underbid labor are not miscounting hours. They are costing direct wages and leaving burden as overhead, which means it never attaches to the specific job that generated it. When burden floats in overhead, you appear to break even on labor while your fixed costs quietly absorb what should have been job margin.
The discipline Greg Crabtree would insist on: burden belongs on the job. Price it there, track it there, and hold the job accountable for the full cost of the labor it consumed. If that changes your bid price, good — that is the correct price.
What Are Committed Costs, and When Should They Hit a Job?
A committed cost is any cost you have contractually obligated but not yet paid — a signed subcontractor agreement, a material purchase order, an equipment rental reservation. For cash-basis books, committed costs are invisible until the invoice arrives. That is a problem.
If your framing sub has a signed $40,000 agreement and has completed half the work, you have a $20,000 cost exposure that your job report does not reflect yet. If you are making decisions — whether to take another job, whether to release a draw, whether a change order is worth pursuing — based on cost-to-date without accounting for what is committed, you are steering with an incomplete instrument panel.
A controller-level process for construction tracks committed costs as a separate column in the job cost report alongside actual costs to date. The working number that matters is not “what have I spent” but “what will this job ultimately cost” — and that requires knowing what is committed.
How Does WIP Accounting Distort Your P&L If You Ignore It?
Work-in-progress accounting is the mechanism that matches revenue recognition to the actual percentage of work completed. Without it, you are recognizing revenue when you bill, not when you earn it — and for contractors, those two things are frequently out of sync.
Overbilling on a job that is behind schedule inflates current-period revenue while the cost to complete that job is still coming. Underbilling on a job that is ahead of schedule suppresses revenue even though you have earned it. When you look at a P&L without proper WIP adjustments, you are not looking at your real profitability — you are looking at a billing-timing artifact.
The practical output of a well-run WIP schedule is an over/under-billing position for every active job, reconciled monthly. Jobs that are consistently overbilled relative to percent complete are warning signs: either the schedule is slipping or costs are coming that have not hit the books yet. Either condition deserves attention before the job closes, not after.
Where Does Change-Order Discipline Fit in Margin Retention?
Change orders are where contractor margin either gets defended or surrendered. The work happens either way. The cost hits either way. Whether you recover that cost — and recover it with appropriate margin — depends entirely on your process for identifying, pricing, and executing change orders before the work is done.
The most common failure pattern: the crew does the work, the owner is happy in the moment, and the contractor intends to document the change order later. Later becomes after substantial completion. After substantial completion, the owner’s posture changes. The change order gets negotiated down or disputed entirely.
The structural fix is procedural, not financial: no out-of-scope work begins without a signed change order. That is a field-level discipline, not an office-level one. If your project managers and foremen are not empowered — and accountable — to hold that line, the policy exists on paper but not in practice.
From a costing standpoint, change orders should also carry the same burden and overhead markup as the original bid. A change order priced at direct cost to “keep the relationship smooth” is a margin subsidy you are extending to your customer, often without realizing it.
What Does a Job Cost Report Actually Need to Show to Be Useful?
A job cost report that only compares budget to actual cost-to-date is a lagging indicator. By the time the overrun is visible, most of the damage is done. A report that supports real decisions needs at minimum:
- Original contract value and revised contract value (approved change orders included)
- Budget by cost category (labor, materials, subcontractors, equipment, other)
- Actual costs to date with burden applied
- Committed costs not yet invoiced
- Estimated cost to complete — a forward-looking projection, not just the remaining budget
- Projected final margin — what the job will actually yield when done
That final margin number, updated monthly for every active job, is the number that changes behavior. When project managers see their projected margin move, they ask different questions on-site. When owners can sort their backlog by projected margin, they know which jobs need attention before the problems become permanent.
How Often Should Job Cost Reviews Actually Happen?
Monthly, at minimum, for every job over a threshold you define — perhaps any job that represents more than a certain percentage of your annual revenue, or any job running longer than 60 days. Weekly for jobs that are flagged as at-risk based on percent-complete variance or committed-cost exposure.
The review is not a bookkeeping exercise. It is a management conversation: what changed, why did it change, and what decision does that require? A job cost report that gets produced but not discussed is a cost, not a tool.
The Compounding Problem: Small Leaks on Many Jobs
A single job running four margin points below budget is recoverable. Ten jobs running four points below budget simultaneously is a structural problem — and it is invisible at the company level until the year-end P&L arrives with a number that does not match anyone’s expectations.
This is why job costing is not a “nice to have” for contractors at scale. It is the primary financial control mechanism. Revenue and backlog tell you about the future. Job cost performance tells you whether that future will actually generate the return the business needs to sustain itself, pay its owner a real market wage, and build toward something.
The contractors who hold margin through growth cycles are the ones who treat the job cost report as a management instrument rather than a compliance artifact.
LPR Business Services works with established contractors through fractional controller and CFO engagements — bringing the job costing infrastructure, WIP discipline, and financial reporting cadence that in-house bookkeeping rarely has the capacity or specialization to maintain. If your financials are producing numbers but not answers, that is the conversation worth having.