WRONG OVERHEAD RATE DISCOVERED AND FIXED TRUE MARGIN VISIBLE BY TRADE TYPE $4.9M CONCRETE SUBCONTRACTOR FLATWORK VS STRUCTURAL — FINALLY SEPARATED JOB PROFITABILITY LIVE WITHIN 60 DAYS WRONG OVERHEAD RATE DISCOVERED AND FIXED TRUE MARGIN VISIBLE BY TRADE TYPE $4.9M CONCRETE SUBCONTRACTOR FLATWORK VS STRUCTURAL — FINALLY SEPARATED JOB PROFITABILITY LIVE WITHIN 60 DAYS
THE CONSTRUCTION CFO SCHEDULE A CALL
CASE STUDY · CONCRETE CONTRACTOR · LAYER 4 PROOF

WRONG OVERHEAD RATE. TRUE MARGIN INVISIBLE.

A $4.9M concrete subcontractor was bidding flatwork and structural work using the same overhead rate. The overhead rate was also wrong — built from a CPA estimate, not actual cost data. CFOS rebuilt the rate from the books, separated margins by work type, and made per-job profitability visible for the first time. What they discovered: structural work was subsidizing flatwork losses they hadn't known existed.

Concrete subcontractor case study. A $4.9M concrete sub was using a wrong overhead rate built from CPA estimates, not actual cost data. Flatwork and structural concrete were being bid at the same overhead rate despite different labor intensity, equipment burden, and margin profiles. CFOS rebuilt the overhead rate from actual financials, separated margins by work type, and made per-job profitability visible within the 60-day onboarding. What they found: flatwork was consistently losing money. Structural work was the profit engine. The bid strategy changed. CFOS is operated by Sulphur Prairie Management, The Construction CFO.

PUBLISHED · MAY 2026 · CONCRETE · $4.9M REVENUE · ANONYMIZED
THE SITUATION

PROFITABLE ON PAPER. LOSING MONEY IN FLATWORK.

The owner ran a $4.9M concrete subcontracting operation doing both flatwork — slabs, sidewalks, driveways, commercial flatwork pours — and structural concrete: foundations, tilt-up walls, elevated slabs on commercial and industrial projects. Two very different types of work with very different labor profiles, equipment requirements, and margin realities.

They were being bid with the same overhead rate. That rate was whatever the CPA had suggested two years ago based on a general construction markup guideline. It hadn't been calculated from the actual cost structure of this specific business. And it had never been separated by work type.

The overall P&L showed a profit. But that number was a blend. Nobody knew if flatwork was profitable. Nobody knew if structural was subsidizing it. The owner bid on everything that came in front of him because he had no tool to decide which work was worth pursuing.

$4.9M
Annual Revenue
2 YRS
Using an Unvalidated Overhead Rate
0
Per-Job Margin Visibility
BLENDED
Overhead Rate — Not Split by Trade Type
THE PROBLEM

WHAT THE OWNER KNEW.

From the owner: "The business makes money. I know that. But I feel like I'm working twice as hard as I should be for what I'm taking home. Something's off but I can't tell you where."

The "something off" was this: the overhead rate he was using to build his bids didn't reflect what the business actually spent on overhead. And even if it had, it was a single rate applied to labor hours across both flatwork and structural — two work types with substantially different labor intensity and overhead demands.

Flatwork crews were running hard. Structural work was producing better margins but the bids were being built the same way. There was no mechanism to see that the flatwork volume was consistently underperforming until the year-end P&L came in. By then, the jobs were gone and the margins were history.

The failure chain: Wrong overhead rate → bids built on incorrect cost assumptions → flatwork underbid against its true cost → flatwork jobs completed at negative real margin → P&L blends flatwork losses into structural profit → the overall number looks fine → nobody changes the bid strategy.

THE DIAGNOSIS

WHAT CFOS FOUND.

FAILURE CHAIN 1

The Overhead Rate Was Built on Guesswork, Not Actual Costs

CFOS rebuilt the overhead rate from two years of actual financial data in the books. Actual G&A, actual equipment overhead, actual supervision costs, actual insurance, actual administrative burden — all pulled from categorized transactions. The rate that came out of this calculation was 11 percentage points higher than the rate the owner had been using. Every bid built on the old rate had been structurally underpriced relative to actual cost. Twelve months of bids. Every one of them.

FAILURE CHAIN 2

Flatwork and Structural Require Different Rates

Flatwork is labor-intensive and crew-heavy — more supervision burden, more equipment per dollar of revenue, less material complexity. Structural concrete has higher material costs but the labor profile is different. A blended overhead rate applied to both means you are systematically overcharging structural work and undercharging flatwork. In a competitive concrete market, overcharging structural costs you bids. Undercharging flatwork wins you jobs you should be turning down.

FAILURE CHAIN 3

No Per-Job Visibility Meant the Problem Compounded Annually

Without job costing aligned to the estimate structure, there was no way to see a flatwork job's actual margin until the year-end. By the time CFOS ran the first variance reports on prior-year jobs, the pattern was clear: flatwork jobs were averaging 4% net margin. Structural jobs were averaging 14%. The business had been doing roughly 60% flatwork by revenue for two years. That imbalance was costing the owner significant profit that was invisible while it was happening.

THE INTERVENTION

WHAT CHANGED DURING ONBOARDING.

WK 1–2

Overhead Rate Rebuilt From Actual Cost Data

CFOS pulled two years of financials and recalculated the overhead rate from actual categorized costs. G&A, equipment overhead, supervision, insurance, administrative — each category calculated as a percentage of direct labor. The rate came out 11 points higher than what had been used. Two separate rates were built: one for flatwork, one for structural.

WK 2–4

Job Costing Structure Built — Aligned to Estimates

ControlQore was set up with separate job cost structures for flatwork and structural work. Labor codes, material codes, equipment codes — all built to match the bid line items by work type. Every active job was set up in the new structure. Prior-year jobs were analyzed against the new overhead rates to establish the margin baseline.

WK 4–8

First Variance Reports — Bid Strategy Adjusted

With the new job costing structure live and the corrected overhead rates applied, the first monthly variance reports ran. Three active flatwork jobs were running over budget against the corrected rate. The owner's bid strategy shifted: flatwork bids were rebuilt using the new rate, which meant some bids came in higher than competitors. The owner started declining flatwork volume that didn't meet margin threshold.

DAY 60

Per-Job Margin Live. Bid Strategy Rebuilt.

Every active job showing real-time margin against correct overhead rates. Monthly variance reports running. Flatwork bid volume selectively reduced. Structural pursuit increased. The owner could now see what the business was actually making — by job, by work type, by crew.

THE OUTCOME

WHAT CHANGED WHEN THE NUMBERS WERE RIGHT.

+11 PTS
Overhead Rate Correction
4%
Actual Flatwork Net Margin (Was Unknown)
14%
Actual Structural Net Margin (Was Unknown)
DAY 60
Per-Job Visibility Live

The business didn't have a revenue problem. It had a visibility problem. Once the overhead rate was correct and job costing matched the estimates, the owner could see what was actually happening in the business. He stopped chasing flatwork volume he was losing money on. He started prioritizing structural work he hadn't fully pursued. That shift — driven by data that now existed — was worth more than any revenue growth would have been.

TIME TO OUTCOME

FROM FIRST CALL TO VISIBILITY: 60 DAYS.

Day one of the CFOS engagement to per-job margin visibility live: 60 days. Overhead rate rebuilt from actual data in week one. Job costing live by week four. First variance reports running by week six.

The owner had been running this business for years without knowing which work type made him money. That's not a management failure — it's a systems failure. CFOS built the system. The owner made the decisions. That's how it works.

WHAT THIS MEANS FOR OTHER CONTRACTORS

IF THIS SOUNDS FAMILIAR.

Concrete contractors who recognize this story usually share these patterns:

Overhead Rate Came From a CPA, Not From Your Books

The number a CPA gives you for overhead is a starting estimate. It needs to be rebuilt from your actual cost structure annually — and it needs to be separated by work type if you do more than one.

Flatwork and Structural Bid the Same Way

Two different labor profiles, two different equipment burdens, one rate. The result: one work type is consistently underpriced. You find out at year-end which one it was.

You Find Out Job Results at Year-End

By the time you know a job lost money, it's been completed, closed, and billed. Job costing that's not live during the job isn't job costing — it's historical accounting.

You Bid Everything That Comes In

Without per-job margin data by work type, there's no framework to selectively pursue the work worth pursuing. CFOS gives you the numbers to make that decision before you bid, not after you complete.

CFOS Benchmarking and Job Profitability modules fix this exact pattern for concrete contractors. See how CFOS is built for concrete contractors →

QUESTIONS ABOUT THIS CASE

FREQUENTLY ASKED.

A $4.9M concrete subcontractor was using an overhead rate built from CPA estimates, not actual cost data, and was applying it identically to flatwork and structural concrete — two work types with substantially different cost profiles. Per-job profitability was invisible. The business was profitable overall but flatwork was consistently underperforming structural, and the owner had no way to see it.
CFOS rebuilt the overhead rate from two years of actual financial data, finding it was 11 percentage points higher than what the owner had been using. Separate rates were calculated for flatwork and structural work. Job costing was rebuilt to match the estimate structure, making per-job variance visible for the first time.
Overhead rate corrected upward by 11 percentage points. Per-job margin visible by day 60. Actual flatwork net margin identified at 4%. Actual structural net margin identified at 14%. Bid strategy rebuilt around these numbers — flatwork volume selectively reduced, structural pursuit increased.
Yes. Wrong overhead rates and blended margin calculations are extremely common in concrete work — especially when a business does both flatwork and structural, or mixes commercial and residential. CFOS Benchmarking and Job Profitability modules are built to separate these and make per-job visibility real. See the concrete contractor operating system for the full architecture.
Josh Luebker — The Construction CFO
Josh Luebker
President · The Construction CFO · Sulphur Prairie Management

Former PM and master electrician. Managed 150+ projects and $300M+ in construction volume. The overhead rate problem is one of the most consistent patterns we see in concrete work — the number was wrong before we arrived almost every time. More about SPM →

RELATED RESOURCES

WHAT TO READ NEXT.

TRADE OS
Concrete Operating System
Why concrete subcontractors lose margin without knowing it — and the CFOS structure that makes every job visible.
CFOS MODULE
Benchmarking System
The module that rebuilt the overhead rate in this case — trade-specific benchmarks that change what you bid and what you decline.
CFOS MODULE
Job Profitability System
How per-job variance reports made flatwork vs structural margin visible for the first time in this engagement.
DIAGNOSTIC
Your Overhead Rate Is Wrong
How to know if your overhead rate was built from guesswork — and what it costs you in bids every year if it was.
SERVICE
Fractional CFO for Construction
What an engagement looks like, what's included at each tier, and how onboarding works in 60 days.

DO YOU KNOW WHAT YOUR
OVERHEAD RATE ACTUALLY IS?

If it came from a CPA and hasn't been rebuilt from your books, it's probably wrong. Schedule a call — 30 minutes.

SCHEDULE A CALL
Run on CFOS Benchmarking Concrete OS Overhead Rate Fix Fractional CFO Bookkeeping Schedule a Call Josh@ConstructionCFO.net
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