Joseph Toppi didn't start his commercial concrete operation already knowing his numbers. He learned them the hard way, the way most concrete subcontractors do. Revenue was coming in. Jobs were getting done. The crew was working. And yet, at the end of the month, the bank account consistently looked worse than it should have for the volume of work being produced.

The problem wasn't the jobs. It was that the jobs weren't being priced to cover what the business actually cost to run. The overhead, every expense that existed independent of any specific project, was either missing from the estimate entirely or estimated from a rule of thumb that had nothing to do with the actual numbers. Once that gap was closed, once the overhead was calculated from the books and applied correctly to every bid, the business performed differently. Margins held. Growth compounded. That discipline was part of what eventually produced a 54% gross profit margin on a 46-person commercial concrete operation.

This article covers overhead costs specifically for commercial concrete subcontractors: what counts as overhead, what the actual categories are, how to calculate your overhead rate correctly, and how to apply it to your estimates in a way that actually recovers your costs rather than simply approximating them.

Why Most Concrete Subcontractors Underestimate Their Overhead

Before getting into the calculation, it's worth understanding why the gap exists in the first place.

Most concrete subcontractors know their direct costs reasonably well. They know what concrete costs per yard. They know roughly what their crews cost per day. They know what their rebar supplier charges and what their formwork materials run. Direct costs are visible because they're tied to specific projects. You can point to the material invoice and trace it to the job it came from.

Overhead is different. It's the cost of running the business itself, not the cost of completing any particular job. And because it doesn't appear on a job-specific invoice, it's easier to forget, undercount, or wave away with a rough percentage pulled from something someone told you years ago.

According to a 2026 contractor overhead analysis, most contractors today are carrying 25 to 45% overhead, not the 10% the old "10 and 10" rule assumed. Using 10% means you're paying overhead out of pocket, not recovering it from jobs. That gap between what the business actually costs to run and what's being recovered through bids is one of the clearest explanations for why concrete subcontractors can be consistently busy and consistently thin on margin at the same time. Knowing your overhead starts with knowing exactly what it is.

What Counts as Overhead: The Full Category List

The working test for overhead is simple. A useful starting test is this: If you would still owe the money even with zero active projects, it's likely an overhead. Your shop rent runs whether you're pouring concrete or not. Your insurance bill doesn't care about your bid calendar. Your truck payments don't pause during slow seasons. These are overhead costs.

For a commercial concrete subcontractor, the overhead categories that consistently show up in the books include:

• Facility costs. Office rent, shop or yard rent, storage facility costs, and any home office allocation if you work from home. These are fixed costs that run every month regardless of project activity.

• Insurance. General liability, commercial auto, workers' compensation, umbrella coverage, and any professional liability or equipment coverage. Insurance is one of the largest and most consistently underestimated overhead items for concrete subcontractors. Workers' compensation can be a significant labor burden for concrete subcontractors, and the actual rate varies considerably by classification, state, payroll, and claims history.

• Vehicle and equipment overhead. Truck and equipment lease or loan payments, fleet insurance, registration, and scheduled maintenance. The distinction matters here: equipment rented specifically for a project is a direct cost. Equipment you own and maintain as part of the business infrastructure is overhead. Fuel may be treated as a direct job cost or overhead depending on how the equipment or vehicle is used and how the company allocates costs.

• Administrative salaries. Any office staff, bookkeeper, project coordinator, or administrative personnel who support the business rather than direct project execution. If you as the owner are spending meaningful hours on estimating, sales, administration, or management rather than direct field work, a portion of your compensation should be allocated to overhead.

• Software and technology. Estimating software, accounting software, project management tools, document storage, communication platforms, and any other subscription-based tools that support business operations.

• Professional services. Accounting fees, legal fees, and any consulting costs that support the business rather than specific projects.

• Marketing and business development. Website costs, advertising, trade association memberships, bid platform subscriptions like ConstructConnect or BuildingConnected, and any direct marketing activity.

• Office supplies and utilities. Phone and internet, office supplies, postage, and any utilities associated with your office or shop.

• Training and safety. OSHA training, safety program development, and any required certifications for supervisory personnel.

• Estimating time. This is the most commonly overlooked overhead cost in concrete subcontracting. If the owner or a salaried employee spends 20 hours per week estimating bids that don't always result in awarded work, that time has a cost. It doesn't belong to any specific project. It belongs to the overhead pool.

The Two Formulas You Need to Run

There are two ways to express your overhead rate, and understanding the difference between them matters for how you use each one.

Formula 1: Overhead as a percentage of revenue

Total Annual Overhead ÷ Total Annual Revenue × 100

This formula tells you how heavy the overhead burden is relative to your top line. According to CFMA benchmark data, small construction companies under $50 million in annual revenue typically run overhead rates of 20 to 25% of revenue. This is the formula you use to understand how your business compares to industry benchmarks and to assess whether your overhead structure is appropriate for your size.

Formula 2: Overhead as a percentage of direct costs

Total Annual Overhead ÷ Total Annual Direct Costs × 100

This is the formula you need for bidding. Because your estimate starts with direct costs, applying overhead as a percentage of direct costs tells you exactly how much to add to recover your overhead on any given project. This is the number that goes into your markup calculation alongside your profit target.

The same contractor can look efficient under one formula and stretched under another. The denominator changes the story, and that's why overhead discussions get messy inside construction firms. Run both formulas. Use the revenue-based version to benchmark your business health. Use the direct-cost-based version to build your bids.

Here's what that looks like with real numbers. A concrete subcontractor doing $3 million in annual revenue with $2.3 million in direct costs and $450,000 in annual overhead runs:

• Overhead rate on revenue: $450,000 ÷ $3,000,000 = 15%

• Overhead rate on direct costs: $450,000 ÷ $2,300,000 = 19.6%

The second number is what gets applied to every estimate. Every bid that goes out needs to recover $0.196 in overhead for every dollar of direct cost, before a single dollar of profit is calculated.

The Overhead Rate Per Billable Hour: A More Precise Tool

For concrete subcontractors who want a more granular view of what their overhead costs per productive hour, the billable hour method provides a useful supplemental calculation.

Industry benchmarks from Deltek Clarity, CFMA, and the Zweig Group put productive billable hours for field crew at 1,600 to 1,800 per employee per year, roughly 133 to 150 hours per month per employee. The gap between hours on the clock and billable production hours, including commute time, yard time, training, safety meetings, rework, and waiting for materials, means these hours consume overhead without generating revenue.

The calculation:

Total Annual Overhead ÷ Total Annual Billable Hours = Overhead Rate Per Billable Hour

For a concrete subcontractor with $400,000 in annual overhead and a crew producing 12,000 billable hours per year, the overhead rate is $33.33 per billable hour. That means every hour your crew is producing work, you need to recover $33.33 above the direct labor cost just to cover overhead before any profit is made.

This calculation is particularly useful for understanding how overhead allocation differs between structural concrete and flatwork. A structural concrete scope with lower crew productivity per hour, because of forming complexity and rebar detailing, carries more overhead burden per unit of production than a high-volume flatwork package. Applying a single overhead rate without accounting for that difference can produce bids that look consistent but are actually under-recovering overhead on structural work and over-recovering it on flatwork.

How to Apply Overhead to a Concrete Estimate

Once you have your overhead rate expressed as a percentage of direct costs, applying it to an estimate is straightforward. After calculating your total direct costs for the project, including materials, labor, equipment burden, and any lower-tier subcontractors, you add your overhead percentage to arrive at your total cost. Then you add your profit margin on top of that total cost to reach your bid price.

The critical distinction here connects directly to understanding markup vs. margin. A 20% markup on direct costs is not the same as a 20% profit margin on revenue. Here's the math on a $500,000 direct cost project:

• Direct costs: $500,000

• Overhead at 18% of direct costs: $90,000

• Total cost: $590,000

• Profit at 10% markup on total cost: $59,000

• Bid price: $649,000

• Gross profit margin on revenue: 9.1%

This is exactly how concrete subcontractors end up winning work at numbers that look profitable and discovering three months into the job that the margins aren't there. The overhead wasn't calculated from the actual books. It was approximated. And the approximation was wrong.

Review and Update Your Overhead Rate Regularly

Overhead isn't static. Insurance premiums increase. You add software tools. You hire an estimating coordinator. Fuel costs rise. A new lease comes in higher than the old one. Any of these changes the overhead pool, and if your bid rate doesn't reflect the current overhead, every estimate you produce is either under-recovering costs or over-pricing relative to your actual burden.

Review your overhead rate at least annually, comparing your estimated overhead against what you actually spent to find discrepancies. A mid-year check is worth doing if you've made any significant changes to the business, including adding staff, changing facilities, renewing insurance, or taking on new equipment. The bids you submit today are pricing work that will be executed months from now. The overhead rate those bids carry needs to reflect what the business will cost to run during that window, not what it cost 18 months ago.

This discipline is part of the financial management framework that separates concrete subcontractors who know their numbers from those who find out what their margins really were at year-end, when it's too late to adjust the bids that produced them. The business metrics that track overhead recovery across active projects, not just annually, are worth building into your regular financial review process.

The Connection Between Overhead and Cash Flow

Understanding your overhead rate doesn't just improve your bids. It directly affects your cash position. When overhead isn't being recovered through project pricing, the shortfall comes from somewhere, and it almost always comes from cash reserves or working capital that the business needs for other purposes.

That connection is why overhead calculation and cash flow management are part of the same financial discipline. A concrete subcontractor whose overhead rate is understated by even 5% on $3 million in annual revenue is leaving $150,000 in unrecovered costs per year that has to come from somewhere. Over two or three years, that gap produces a business that's working hard, winning work, and slowly depleting the financial cushion it needs to grow.

The overhead calculation is also relevant to the in-house estimator vs. outsourcing decision. A full-time estimating hire adds $115,000 to $150,000 to your annual overhead pool, which changes your overhead rate and therefore every bid you produce going forward. That cost has to be factored into the decision before the hire is made, not discovered after the salary starts running.

At Stancon Consultants, helping commercial concrete subcontractors understand their actual cost structure is part of how we build estimates that hold up in the field rather than producing numbers that look right on bid day and deteriorate through execution. Our concrete estimating services are built on your actual cost structure, including a correctly calculated overhead rate, not on generic assumptions. And if you want to build out the ongoing estimating infrastructure that keeps those numbers current as the business grows, our fractional estimating plans are structured around exactly that.

Conclusion

Overhead isn't just an accounting number. It determines whether the prices you're putting into the market are actually capable of producing the margins you expect. If your overhead rate is based on an outdated percentage or a rule of thumb, every bid you submit carries the risk of under-recovering the true cost of running your business.

The solution is to know your actual overhead, update it regularly, and build it deliberately into every estimate. When your overhead recovery, markup, and profit targets are based on real numbers, you can bid with greater confidence and make better decisions about which work is worth pursuing.

We help commercial concrete subcontractors build estimates around their actual costs, including overhead, labor, materials, and production requirements. If you're not confident that your current bids are fully recovering the cost of running your business, let's talk about how we can help you build a more reliable estimating process.