In construction, overhead refers to all the costs of running a business that aren’t tied to the physical work on a job site. These are expenses like office rent, insurance, staff salaries, and software licenses that a construction company pays whether or not any particular project is underway. The industry sometimes calls this the cost of “keeping the lights on.” Overhead is separate from hard costs (the labor, materials, and equipment that go directly into building something), but it gets factored into every project bid so the company can stay profitable.
Overhead vs. Hard Costs
Hard costs, also called direct costs, are the expenses you can point to on a job site: lumber, concrete, the wages of the crew pouring a foundation, the crane rental for lifting steel beams. If the project didn’t exist, these costs wouldn’t exist either.
Overhead is everything else the company needs to spend to operate. Even though project managers and superintendents may be on site, the overall cost of running the business still generates monthly expenses regardless of that particular project. A construction firm with zero active jobs still owes rent, still pays its accountant, and still carries insurance. Those fixed obligations are the core of overhead.
Common Overhead Expenses
Overhead in construction typically includes:
- Office rent or mortgage for the company’s main location
- Administrative salaries for office staff, estimators, and bookkeepers who aren’t billing to a single job
- Insurance including general liability, workers’ compensation, and vehicle coverage
- Accounting and legal fees
- Tools and general equipment not charged to a specific project
- Software and technology such as project management platforms, construction accounting programs, CAD tools, and Building Information Modeling (BIM) licenses
- Vehicles and fuel for company trucks used across multiple jobs
- Marketing and business development
Technology has become a growing slice of overhead. Modern construction firms rely on project tracking systems, estimating software, and digital collaboration tools that carry subscription or licensing costs year-round. These expenses didn’t exist a generation ago, but they’re now standard line items in most overhead budgets.
Typical Overhead Percentages
The most widely cited benchmark is the 10-10 rule from the National Association of Home Builders: 10% overhead and 10% net profit, producing a 20% total markup on direct costs. In practice, those numbers shift depending on the type of work and the size of the company.
Residential contractors generally run overhead between 10% and 15%, with net profit margins of 10% to 20%. Commercial contractors tend to carry higher overhead, ranging from 12% to 20%, because their projects involve more administrative complexity, bonding requirements, and longer timelines. Their profit margins typically fall between 5% and 15%. Specialty subcontractors often have the highest overhead of all, in the 15% to 25% range, partly because specialized labor, certifications, and niche equipment cost more to maintain. Their total markup (overhead plus profit) can reach 25% to 50%.
A 10% overhead rate is a reasonable starting point for a small residential operation, but larger or more complex projects generally push that number higher.
How Overhead Gets Allocated to Projects
Since overhead belongs to the whole company rather than any single job, contractors need a method for spreading it across their projects. There are several common approaches, and the right one depends on how the company works.
Percentage of Direct Labor Hours
This is one of the most straightforward methods. You divide total annual overhead by total estimated labor hours to get a rate per hour. If a company expects $1 million in overhead and 50,000 labor hours in a year, the overhead rate is $20 per labor hour. A job requiring 1,000 labor hours would absorb $20,000 in overhead. This works well when labor is the primary driver of project costs.
Percentage of Direct Costs
Here, you express overhead as a percentage of all direct project costs. If total overhead is $1 million and total direct costs across all jobs are $5 million, the overhead rate is 20%. A project with $100,000 in direct costs picks up $20,000 in overhead. This method is simple and works for companies with a fairly consistent mix of labor and materials across projects.
Square Footage
For projects where size is the main variable, overhead can be allocated per square foot. If total overhead is $100,000 and the company is building 50,000 square feet across all jobs, a 5,000-square-foot project would carry $10,000 in overhead. This is common in residential building where homes of similar type vary mainly by size.
Machine Hour Rate
Equipment-heavy work like earthmoving or heavy civil construction sometimes allocates overhead based on machine hours. Projects that use more equipment absorb a larger share of overhead, which better reflects their actual demand on company resources.
Activity-Based Costing
This is the most detailed approach. The company breaks overhead into categories (project management, procurement, safety administration) and tracks how much of each activity a given project consumes. If project management accounts for 40% of total overhead and a particular job uses 20% of management time, that job gets 20% of the project-management overhead. It’s more accurate but requires more bookkeeping.
Overhead, Markup, and Your Final Price
When a contractor bids on a project, the estimate starts with hard costs: materials, labor, subcontractors, equipment rental. Overhead and profit are then layered on top. Together, overhead and profit form the markup.
If a contractor’s overhead rate is 25% and the desired profit margin is 10%, the total markup component is 35%. On a job with $200,000 in direct costs, that means $50,000 for overhead and $20,000 for profit, bringing the bid to $270,000. The overhead portion isn’t extra money the contractor pockets. It covers the real costs of the office, the estimator who spent two weeks pricing the job, the insurance policy that protects the homeowner, and every other behind-the-scenes expense that makes the project possible.
There’s an important distinction between markup and margin. Markup adds overhead and profit on top of costs. Margin expresses those same dollars as a percentage of the final selling price. The math produces different numbers, and contractors who confuse the two can underprice their work and lose money even on busy jobs.
Why Overhead Matters to Homeowners and Developers
Understanding overhead helps you read a construction estimate more clearly. A bid that looks cheap may simply be a contractor who hasn’t accounted for overhead properly, which raises the risk of cost overruns, corners cut, or a company that goes under mid-project. A reasonable overhead percentage is a sign that the contractor runs a stable business with proper insurance, competent office staff, and the resources to manage your project from start to finish.
If you’re comparing bids and one is significantly lower than the others, it’s worth asking how the contractor covers their operating costs. The answer tells you a lot about whether that price is sustainable or whether problems are likely to surface once the work is underway.