A construction contractor is the single party who signs a contract with the property owner and takes responsibility for delivering the finished building. That means planning the work, hiring and paying the trades, buying materials, pulling permits, running the site day to day, passing inspections, and standing behind the result under warranty. So what does a construction contractor do in practical terms? Everything between the architect’s drawings and the certificate of occupancy, with legal and financial accountability for all of it.
Plans the Job and Owns the Budget
Once the owner says go, the contractor turns blueprints into a work plan. That means sequencing the trades, setting milestones, and building a master budget tracked against the contract price. On well-defined projects, a contingency allowance of 5 to 10 percent of base cost absorbs surprises like bad soil, material price jumps, or design errors; on fuzzier scopes, the cushion can run 15 percent or more.
The schedule is the governing document for the whole site. Milestones such as foundation completion, framing, and mechanical rough-ins often tie directly to progress payments. Falling behind can trigger liquidated damages, which are preset financial penalties written into the contract. They are meant to compensate the owner for actual anticipated losses from delay, not to punish.1Acquisition.GOV. Subpart 11.5 – Liquidated Damages On larger commercial and government jobs, daily liquidated damages of $1,000 or more are common.
Change Orders
No project runs exactly to plan. When the owner adds a window, the architect catches a code conflict, or workers hit an unmapped utility, the contractor runs the change order process. A change order is a formal contract amendment that documents how scope, cost, and timeline are shifting. The contractor quantifies the impact, gets revised drawings where needed, and secures the owner’s written approval before extra work begins. Change orders typically add about 3 to 5 percent to the original contract value, and on some jobs they push costs up by 15 percent or more. A contractor who approves extra work verbally or fails to document scope changes is building a dispute that can outlast the project.
Hires and Manages the Trades
General contractors rarely do all the physical work themselves. They hire licensed subcontractors in electrical, plumbing, HVAC, roofing, concrete, and other trades. Before anyone starts, the contractor checks licenses, reviews certificates of insurance for general liability and workers’ compensation, and looks at the sub’s track record. Bringing on an uninsured subcontractor who injures someone on site can expose the general contractor to catastrophic liability.
Subcontract agreements spell out the scope, payment schedule, and risk allocation. Many address how payment flows from the owner through the general contractor to the sub. “Pay-when-paid” clauses require payment within a reasonable time after the owner pays. “Pay-if-paid” clauses go further and shift the entire risk of owner nonpayment onto the subcontractor. State law treats these clauses differently, and the distinction matters most when an owner stops paying.
Day to day, the contractor is the single point of contact between the owner and every crew on site. The plumber needs the wall open; the framer wants it closed. The electrician is behind, which blocks drywall. The contractor resolves these conflicts so the owner never deals with a dozen separate firms. That coordination is arguably the most valuable thing a general contractor provides.
Buys Materials and Schedules Equipment
Materials have to arrive on time, in the right quantity, at the right price. The contractor negotiates with lumber yards, concrete plants, and suppliers, issues purchase orders, and times deliveries to the schedule. Materials that arrive too early need storage and can deteriorate in weather. Materials that arrive late halt production and waste the crew’s day.
Heavy equipment follows the same logic. Excavators, cranes, scaffolding, and lifts have to be rented, delivered, and pulled on a precise schedule. Daily rental runs from a few hundred dollars for smaller machines like skid steers to well over $1,000 for heavy cranes, so keeping a crane on site an extra week because a phase slipped is a direct hit to the budget.
Handles Permits, Inspections, and Code Compliance
Before anyone swings a hammer, the contractor deals with the local building department. That starts with permit applications, which require detailed plans and fees that typically run between 1 and 3 percent of total project value under standardized valuation tables. Working without a permit risks a stop-work order and daily fines.
Throughout construction, the contractor coordinates mandatory inspections at the foundation, framing, electrical rough-in, plumbing, and final stages. At each one, the contractor walks officials through the work to show it meets local building codes. A failed inspection means rework, delay, and re-inspection, usually at the contractor’s expense when the cause was poor workmanship or supervision.
OSHA Safety
Federal safety rules under 29 CFR Part 1926 apply to every construction site in the country.2eCFR. 29 CFR Part 1926 — Safety and Health Regulations for Construction The contractor implements these standards, covering fall protection, scaffolding, excavation, hazard communication, and more. OSHA can inspect any site, and the penalties are steep: up to $16,550 per serious violation and up to $165,514 for willful or repeated violations as of 2025.3Occupational Safety and Health Administration. OSHA Penalties A single inspection can produce a six-figure citation package. Writing a safety plan is not enough; the contractor has to enforce it every day.
Stormwater and Environmental Rules
Any site that disturbs one acre or more triggers a federal Clean Water Act permit and a Stormwater Pollution Prevention Plan, commonly called a SWPPP.4US EPA. Stormwater Discharges from Construction Activities The plan has to address erosion and sediment controls, stabilization of disturbed areas, and prohibition of pollutant discharges such as concrete washout water, fuels, and solvents.5US EPA. Construction General Permit (CGP) Frequent Questions Smaller sites that are part of a larger development also trigger coverage. The contractor installs and maintains silt fences, sediment basins, and other controls through the life of the project.
Energy Code
Energy codes are tightening, and the contractor is on the hook for insulation values, air sealing, and equipment efficiency as those requirements change. Getting it wrong does not just fail an inspection; it can require tearing out and redoing completed work.
Carries the License, Bond, and Insurance
Most states require general contractors to hold a license, registration, or certification before performing construction work. Some require passing an exam and showing financial responsibility; others require registration above a dollar threshold; a few have no state-level requirement, though local jurisdictions in those states often impose their own. Working without the required license can mean fines, inability to enforce contracts in court, and, depending on the state, criminal charges.
Surety Bonds
On federal construction projects over $150,000, the contractor must post both a performance bond and a payment bond before the contract is awarded.6Acquisition.GOV. 28.102-1 General A performance bond guarantees completion according to contract; if the contractor defaults, the surety steps in to finish the work or compensate the owner. A payment bond guarantees that subcontractors, suppliers, and laborers are paid, which protects the owner from mechanic’s lien claims. The federal requirement is codified at 40 U.S.C. ยง 3131.7Office of the Law Revision Counsel. 40 US Code 3131 – Bonds of Contractors of Public Buildings or Works Many state and local governments impose similar bonding on public projects, and private owners on larger jobs often require them too.
Insurance
General liability insurance covers bodily injury and property damage claims from third parties. Workers’ compensation is required in virtually every state for employees. Builder’s risk insurance covers damage to the structure itself during construction from events like fire, wind, and theft of materials. The contractor typically coordinates who carries the builder’s risk policy, whether owner or contractor, and makes sure the limits match the project value.
Supervises the Work and Delivers the Finished Building
The contractor is on site daily, and this is where the plan meets reality. They inspect work in progress to confirm that materials, dimensions, and installation methods match the approved specifications. Catching a framing error or a misrouted pipe at rough-in costs a few hundred dollars. Catching it after drywall is up and finished costs thousands.
Quality assurance ends with a final walkthrough. The contractor assembles a punch list of minor repairs, cosmetic touch-ups, and unfinished items that have to be cleared before the project is considered complete. Clearing the punch list is usually the prerequisite for release of retainage, a percentage of each progress payment the owner holds back as leverage. Retainage commonly runs 5 to 10 percent of total contract value. On a $500,000 project, that is $25,000 to $50,000 the contractor does not collect until the owner is satisfied.
Once the punch list is clear and all inspections pass, the contractor obtains the certificate of occupancy from the local building department. That document confirms the building complies with applicable codes, all inspections have passed, and the structure is legally safe to occupy. No one moves in until it issues.
Stands Behind the Work After Completion
The contractor’s obligations do not end at move-in. Most construction contracts include a warranty period during which the contractor returns to fix defective work at no additional charge. On federal projects the standard warranty is one year from final acceptance, and any repaired or replaced work restarts its own one-year clock.8Acquisition.GOV. 52.246-21 Warranty of Construction Private contracts commonly follow the same one-year framework, though the duration can be negotiated. Warranties cover defects in materials, equipment, and workmanship, and generally do not cover owner misuse or normal wear and tear.
Latent defects, problems hidden behind walls or underground that do not surface until years later, can extend liability past the express warranty depending on state law. A roof that starts leaking 18 months after completion because of bad flashing may still be the contractor’s problem even after the one-year warranty has technically expired. The contractor who can show exactly what was installed, when, and by whom is in a far better position to resolve or defend against the claim.
Protects the Right to Get Paid
Payment is a persistent problem in construction. Money flows from the owner to the general contractor to subcontractors and suppliers, and a break anywhere in that chain creates problems downstream. Two legal tools exist specifically to protect contractors who are not paid.
The first is the mechanic’s lien, a legal claim that attaches to the property the contractor improved. Every state has its own statute, and filing deadlines, notice requirements, and enforcement procedures vary. The core principle is consistent: if you furnished labor or materials to improve a property and were not paid, you can place a lien on that property. The lien clouds title, making it hard for the owner to sell or refinance until the debt is resolved, and that leverage is often enough to prompt payment without litigation. Missing the filing deadline, which can be as short as 60 days after the last day of work in some states, forfeits the right entirely.
The second tool is the payment bond. On bonded projects, an unpaid subcontractor or supplier can file a claim against the bond rather than lien the property. This matters most on public projects, where government property generally cannot be liened at all.