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How a $6M Contractor Was Losing $40K/Month and Didn't Know It

A construction company with 8 active projects was leaking margin on every job. A fractional controller engagement uncovered $480K in annual losses and rebuilt their WIP process in 90 days.

By Stuart Wilson, ACMA CGMA · · 17 min read
TL;DR — Case Study Summary

A $12M general contractor ("Summit Builders") was losing approximately $40,000 per month to margin fade across five active projects. A week-one project-by-project margin analysis revealed three projects with margin fade exceeding 15%, one project operating at a net loss, and $380K in unapproved or unbilled change orders. Within 90 days, implementing weekly WIP reporting, phase-level job cost tracking, a formal change order management process, and a 13-week cash flow forecast tied to project milestones recovered the lost margin, resolved the unbilled change orders, and secured a bank line of credit increase. The owner now receives a one-page project dashboard every Monday morning.

$40K/mo
Margin Fade Recovered
$380K
Unbilled Change Orders Resolved
90 Days
Time to Full Implementation
5 → 0
Projects with Untracked WIP

The Phone Call

Mike didn't call because he wanted a fractional controller. He called because his bank had just put a soft hold on his $500K line of credit, and he had payroll in nine days.

Summit Builders — a general contractor operating across the Front Range of Colorado — had closed $12.4M in contracts the previous year. They'd won good work: a $3.2M mixed-use renovation, a $2.8M medical office build-out, a handful of mid-range commercial projects. Mike had been in the trades for 22 years. He knew how to estimate, how to manage subs, how to keep owners happy. What he didn't know was why his bank account kept dipping below $60K despite the fact that his bookkeeper, Lisa, told him every month that they were profitable.

"We bill $900K a month," Mike told me on that first call. "Our P&L shows 18% gross margin. But I'm floating payroll on a credit card every other cycle. Something's broken, and I can't see it."

🚩 Warning Sign

When your P&L says profitable but your bank account disagrees, the problem is almost never revenue. It's cost recognition — specifically, how and when job costs are matched to revenue on active projects. In construction, this is the WIP schedule. Most contractors under $25M don't have a real one.

Lisa was competent. She reconciled bank statements on time, kept vendor files clean, and ran payroll without errors. But she was a bookkeeper — not a controller. She had no training in percentage-of-completion accounting, no framework for tracking work-in-progress, and no understanding that the numbers she was reporting to Mike were structurally wrong. This wasn't Lisa's fault. It was a systems failure — and it was costing Summit roughly $40,000 every single month.

What We Found in Week 1

I spent the first five days doing one thing: pulling every active project out of Summit's accounting system and rebuilding the numbers from the ground up. Contract value. Original estimated cost. Actual cost-to-date. Billings-to-date. Remaining cost to complete. I wasn't looking for fraud or incompetence. I was looking for the gap between what Summit thought their margins were and what the margins actually were.

The gap was enormous.

Project-by-Project Margin Analysis

Project Contract Value Original Margin Current Margin Margin Fade Status
Ridgeline Medical $2,840,000 22.0% 4.3% −17.7% 67% complete
Apex Mixed-Use $3,220,000 19.5% −2.1% −21.6% 48% complete
Front Range Office $1,960,000 24.0% 21.8% −2.2% 82% complete
Cedar Park Retail $2,450,000 20.0% 3.6% −16.4% 55% complete
Southgate Industrial $1,930,000 18.0% 17.1% −0.9% 91% complete

Three of five projects had margin fade exceeding 15 percentage points. The Apex Mixed-Use job — Summit's largest active project — was losing money, and nobody in the company knew. Mike was bidding these jobs at 18–24% gross margin. He was delivering them at 4%, at break-even, or at a loss.

3 of 5
Projects with >15% Margin Fade
−2.1%
Actual Margin on Largest Project
18%
Material Cost Overrun (3 Projects)

The material cost overruns jumped out immediately. On the three bleeding projects, lumber, steel, and concrete costs were running 18% above the original estimate. Some of that was market movement — supply chain costs had ticked up 6–8% since the bids went out. But the remaining 10–12% was scope creep that had never been captured in a change order, rework from subcontractor errors that hadn't been back-charged, and material waste that nobody was tracking at the project level.

Why This Matters
In construction, a 1% margin fade on a $3M project is $30,000 — gone. When you're fading 15–20% across multiple jobs simultaneously, the cash impact compounds faster than most owners realize. By the time the bank account tells the story, you're already six months behind.

The subcontractor overruns were the second-largest leak. Summit's PMs were approving sub invoices without comparing them against the original subcontract value. On the Ridgeline Medical project alone, the electrical sub had billed $87,000 over the contract amount — across 14 separate invoices — and every one had been paid without question. The PM assumed the sub was billing for approved extras. The sub assumed the PM had approved the scope changes. Nobody had documented anything.

The Hidden $380K

The change order problem was the worst finding. It was also the most fixable.

When I compiled every scope modification, owner-directed change, and field condition across all five projects, I found $380,000 in change orders that were either unapproved, unbilled, or both:

  • $142,000 in completed change order work that had never been billed to the project owner
  • $118,000 in owner-requested changes with verbal approval but no signed CO document
  • $86,000 in field conditions that qualified for change orders but were never submitted
  • $34,000 in approved COs billed at the original rate instead of the adjusted rate
💡 Key Insight

In construction, change orders aren't just a billing mechanism — they're a margin protection system. Every hour of extra work that doesn't become a signed, billed change order is money you've donated to the project owner. Summit was making $380K in donations they didn't know about.

The root cause was cultural, not technical. Mike ran his business on handshakes and trust. When an owner asked for a design modification mid-build, the PM would say "sure, we'll work it out." The work got done. The paperwork didn't. And by the time anyone circled back to price the change, the leverage was gone — you can't send a change order for work completed three months ago and expect a clean approval.

The $142K in unbilled completed work was the most painful number. That work was done. The costs were incurred. Summit had paid labor, materials, and subs for scope that was never billed to the customer. It was pure margin destruction — and it showed up nowhere in Lisa's reports because the costs were buried in the project actuals with no offsetting revenue.

📊 By the Numbers

The $380K in unprocessed change orders represented 3.1% of Summit's total annual revenue. For a company targeting 20% gross margin, that's roughly 15% of total expected profit — evaporating silently before it ever hits the bank account.

The Fix: Four Systems in 90 Days

There's no single tool or software that solves margin fade. It's a systems problem, and it requires a systems response. Over 90 days, we built and implemented four interlocking processes. None of them were revolutionary. All of them were necessary.

System 1: Weekly WIP Reporting

The WIP schedule is the single most important financial document in a construction company. It tells you, for every active project, exactly where you stand: how much you've earned, how much you've billed, how much you've spent, and what's left. Most contractors under $25M either don't have one or update it quarterly. Summit had never produced one at all.

We built a WIP schedule in the first two weeks. It tracked every active project across seven key metrics: contract value (including approved COs), estimated cost at completion, cost to date, percent complete (cost method), earned revenue, billings to date, and over/under billing position.

Every Friday by 2 PM, project managers submitted cost-to-complete estimates. I reconciled them against actuals, flagged variances greater than 5%, and produced the WIP by end of day. The report was on Mike's desk Monday morning. Within three weeks, he could look at a single page and know which projects were healthy, which were slipping, and which needed intervention.

✅ What Changed

Before: Mike found out about margin problems at month-end — or never. The bank found out before he did.
After: Problems surface within 5–7 days. Mike has time to course-correct before a slipping project becomes a bleeding one.

System 2: Job Cost Tracking by Phase

Summit was tracking job costs at the project level — one bucket per project. That's like managing a household budget with a single line item called "spending." You know the total, but you have no idea where the money is going.

We restructured the chart of accounts to track costs by phase: pre-construction, site work, foundation, structural, MEP, finishes, and closeout. Each phase carried its own budget, and every cost — every invoice, timecard, and material receipt — was coded to a specific phase.

This gave PMs a heat map. When the MEP phase on Ridgeline Medical hit 90% of budget at 65% completion, it showed up immediately. Instead of discovering a $120K overrun at project end, the PM flagged it at $40K over and negotiated a back-charge against the electrical sub. That single catch saved Summit $80K in unrecoverable cost.

From the Field
Phase-level job costing isn't new. Every contractor above $50M does it. But in the $5–25M range, most companies resist it because it feels like overhead. It's not overhead — it's the difference between managing your projects and hoping they work out.

System 3: Change Order Management

We implemented a five-step change order process that took less than 15 minutes per change:

  1. Identify — Any scope change gets logged in a CO tracker within 24 hours. No exceptions.
  2. Price — PM prices the change within 48 hours using standardized markup rates.
  3. Submit — CO proposal goes to the owner with full backup. The project doesn't absorb the work until the CO is submitted.
  4. Track — Every CO carries a status: submitted, approved, rejected, or billed. The CO log is part of the weekly WIP review.
  5. Bill — Approved COs hit the next billing cycle. No approved CO sits unbilled for more than 30 days.

The critical cultural shift: previously, PMs did the work first and submitted the CO later (or never). We reversed that. No signed CO, no work starts. For emergency field conditions, we built a 72-hour expedited track — but documentation still came first.

24 hrs
Max Time to Log a Change
48 hrs
Max Time to Price a CO
30 days
Max Time from Approval to Billing
15 min
Average Per-CO Processing Time

Within 60 days, the $380K backlog was resolved. Of the $142K in unbilled completed work, Summit recovered $119K. The $118K in verbally approved changes were formalized and billed within 45 days. The $86K in field conditions were submitted, and $71K was approved.

System 4: 13-Week Cash Flow Forecast

The bank wanted to see that Summit could manage cash, not just revenue. A 13-week cash flow forecast was the tool that made this visible — both internally and to the lender.

We built the forecast around project milestones rather than accounting periods. Every anticipated billing, sub payment, material purchase, and payroll cycle was mapped to a specific week. The forecast updated every Monday as part of the WIP review.

The first version revealed why Mike was struggling: Summit's billing cycle lagged its cost cycle by 23 days. They'd pay subs and labor in week 1, bill the owner in week 3, and collect in week 7. On a $2.8M project, that gap meant Summit was floating $200–300K in unbilled work — funded entirely by the line of credit.

We tightened the billing cycle by shifting to twice-monthly billing tied to completion milestones instead of calendar dates. The cash gap shrank from 23 days to 12. The LOC balance dropped by $180K in the first 60 days.

📐 The Math

Reducing the billing lag from 23 to 12 days on $900K/month in revenue freed up approximately $330K in working capital over 90 days. That's not new revenue — it's cash that was always earned but stuck in the billing pipeline.

The Numbers 90 Days Later

Ninety days after that first phone call, Summit Builders was a different financial operation. Same projects, same team, same market — but radically different visibility and control.

$40K/mo
Monthly Margin Recovered
$380K
Change Orders Resolved
$180K
LOC Balance Reduction
1 Page
Monday Morning Dashboard

Before & After: Key Metrics Comparison

Metric Before After (90 Days) Change
Average project gross margin 8.9% 18.4% +9.5 pts
Projects with margin fade >10% 3 of 5 0 of 5 Eliminated
Unbilled change orders $380,000 $12,400 −97%
Average billing lag (days) 23 days 12 days −48%
Line of credit utilization 94% 58% −36 pts
WIP reporting frequency Never Weekly Implemented
Cash flow forecast horizon None 13-week rolling Implemented
Time to flag a cost overrun 30–60 days 5–7 days −85%
Bank line of credit status Soft hold ($500K) Increased to $750K +50%

The bank didn't just release the hold — they increased the line from $500K to $750K. The credit analyst told Mike it was the 13-week forecast and the WIP schedule that made the difference. "We've never seen reporting like this from a contractor your size," she said. That's not a compliment to Summit. It's an indictment of the industry — and an opportunity for every contractor willing to build better financial systems.

✅ The Ripple Effect

The $380K in resolved change orders didn't just improve margins — it funded the LOC paydown, eliminated the payroll-on-credit-card cycle, and gave Mike negotiating leverage on his next bid. When your financials are clean, everything else gets easier.

What Mike Says Now

"I used to check my bank balance every morning with a knot in my stomach. Now I check the Monday dashboard and actually know where we stand — on every project, every dollar. The WIP schedule alone paid for everything ten times over. I didn't know what I didn't know, and that ignorance was costing me $40K a month." — Owner, $12M General Contractor (name changed for confidentiality)

What Mike won't tell you — because most owners won't — is that the hardest part wasn't the financial systems. It was the cultural change. Making PMs document change orders before doing the work. Making subs submit backup with every invoice. Making himself sit down every Monday and read the WIP. The systems are straightforward. The discipline is what transforms the business.

Why This Keeps Happening

Summit's story isn't unusual. In my experience working with contractors in the $5–25M range, some version of this problem exists in roughly seven out of ten companies. The details vary. The pattern doesn't.

Here's why construction companies are uniquely vulnerable to margin fade:

  • Long project cycles create lag. A 12-month project can hide six months of margin erosion before anyone notices. By the time the final job cost report arrives, the money is long gone.
  • Revenue recognition is complex. Percentage-of-completion accounting isn't intuitive, and most bookkeepers aren't trained in it. Cash-basis or billing-based recognition can mask massive over- or under-billing positions.
  • Change orders are culturally resistant. Contractors build relationships on trust. Stopping work to document a change feels adversarial. But undocumented changes are the single largest source of margin destruction in the industry.
  • Sub management is decentralized. PMs approve invoices in the field with limited visibility into cumulative spend. A $5K overage across 14 invoices becomes an $87K problem nobody saw building.
  • The bookkeeper-controller gap is real. A good bookkeeper handles compliance and data entry. A controller handles analysis and strategic reporting. Most $5–25M contractors have the former and need the latter — but can't justify a $150K full-time hire.
💰 The Fractional Advantage

A fractional controller gives you the analytical horsepower of a $150K hire at a fraction of the cost — typically 30–40% of a full-time equivalent. For Summit, the engagement cost was less than one month's worth of the margin they were losing. The ROI wasn't measured in months — it was measured in weeks.

The contractors who avoid this trap share three traits: they track WIP weekly, they treat change orders as non-negotiable documentation events, and they have someone whose job is to stare at the numbers and ask hard questions. If you don't have that person, you're flying a $12M business with no instruments.

If any part of this story sounds familiar — if you're profitable on paper but short on cash, if your bank is asking questions you can't answer, if you suspect your margins are fading but can't prove it — the problem is almost certainly solvable. It's a systems problem. And systems problems have systems solutions.

The only question is how much margin you burn before you build those systems.

SW

Stuart Wilson

ACMA CGMA — Fractional CFO & Controller

Stuart is the founder of BlackpeakCFO, where he provides fractional controller and CFO services to construction firms, professional services companies, and growth-stage businesses. Before launching his advisory practice, Stuart spent over a decade in institutional finance — including roles at Citigroup, ABN AMRO, and Arle Capital Partners (now Bancroft Group) — managing portfolios, leading financial restructurings, and building reporting frameworks for complex, multi-entity operations. He holds the ACMA and CGMA designations from the Chartered Institute of Management Accountants and brings a rare combination of institutional-grade rigor and operational pragmatism to every engagement.

🏦 Ex-Citigroup · Ex-ABN AMRO
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