Construction Insurance: GL, Builder's Risk, Workers' Comp, and More Explained

Construction is one of the most heavily insured industries in the economy — and for good reason. Projects involve heavy equipment, complex sequencing, multiple parties, and work that can damage property or injure people. Understanding what the main coverage types protect against, what limits are typical on commercial projects, and how your specific project scope drives your risk exposure is essential before signing any contract.

This guide covers the four coverage types required on most commercial construction projects: general liability, builder's risk, workers' compensation, and professional liability — plus the certificate and additional insured requirements you'll encounter on every job.

1. Commercial General Liability (CGL)

General liability is the baseline coverage every contractor must carry. It covers bodily injury and property damage claims arising from construction operations — a worker dropping material that injures a bystander, a subcontractor accidentally breaking a water main, damage to an adjacent building during excavation.

What it does NOT cover:

• • The contractor's own work product (faulty workmanship that requires rework is a warranty/contract issue, not a GL claim)
• • Damage to property in the contractor's care, custody, or control
• • Professional errors and design negligence (separate E&O coverage)
• • Worker injuries (workers' comp)
• • Damage to the project itself under construction (builder's risk)

Completed operations: The "products/completed operations" component is critical — it covers claims that arise after the project is complete. A building collapses two years after turnover due to a construction defect. The contractor's CGL completed operations coverage responds. Most contracts require this coverage to be maintained for 2-10 years after project completion.

Additional Insured Requirements

Owners almost universally require GCs to name them as additional insureds on the CGL policy. GCs pass this requirement down to subcontractors. An additional insured endorsement extends the policy's coverage to the named party for their liability arising out of the contractor's operations. Certificate of Insurance (COI) plus the actual endorsement form (CG 20 10/20 37 are the standard forms) must be provided — a certificate alone is not sufficient.

2. Builder's Risk (Course of Construction)

Builder's risk covers the project itself — the structure under construction — against physical loss or damage from fire, weather, vandalism, theft, and other covered perils during the construction period. Once the project is substantially complete and turned over to the owner, builder's risk typically terminates and the owner's property insurance takes over.

Who carries it matters: The contract must specify whether the owner or GC procures builder's risk. If the owner carries it, the GC and subs are typically named as additional insureds. If the GC carries it, the premium cost is typically included in the GMP or bid price. Ambiguity about who carries it — and gaps in coverage during transition periods — have produced major disputes and uncovered losses.

Coverage gaps to watch for:

• • Flood and earthquake — typically excluded from standard builder's risk, require separate endorsements or policies
• • Existing structures — renovation projects need coverage extended to the existing building, not just new work
• • Stored materials off-site — builder's risk typically covers materials on-site or in transit; materials at a storage yard may need separate coverage
• • Design errors — builder's risk doesn't cover damage caused by faulty design; that's professional liability

3. Workers' Compensation

Workers' compensation provides medical benefits and wage replacement to employees injured on the job, regardless of fault. It also protects employers from lawsuits by injured workers — workers' comp is generally the exclusive remedy for workplace injuries in most states, meaning an injured employee cannot sue the employer in tort.

Experience modification rate (EMR/MOD): Your workers' comp premium is multiplied by your experience modification rate — a factor based on your three-year claims history relative to industry average. An EMR of 1.0 is average. An EMR of 0.75 means 25% below average claims (lower premium). An EMR above 1.0 means above-average claims, and EMRs over 1.25 can disqualify you from bidding on certain public projects.

Subcontractor compliance: GCs are responsible for verifying that all subcontractors carry workers' comp. If a sub doesn't carry coverage and an employee is injured, the GC can be held responsible under "statutory employer" provisions in some states. Always obtain certificates before subs start work — and audit them periodically.

4. Professional Liability (Errors & Omissions)

Professional liability — also called E&O or design errors and omissions — covers claims arising from negligent professional services: design errors, specification mistakes, incorrect engineering calculations, or advice that causes financial loss. Standard CGL does not cover professional acts.

Claims-made vs. occurrence: CGL is an occurrence policy — coverage is triggered by when the incident occurred, regardless of when the claim is filed. Professional liability is typically claims-made — coverage is triggered by when the claim is filed. If the policy lapses before a claim is filed (even for an incident that occurred during the policy period), there's no coverage. This is why tail coverage (extended reporting period endorsements) is critical for design professionals.

Design-build and CM-at-risk: When a contractor takes on design responsibility, their CGL no longer covers the design exposure. Design-build GCs need either contractor's professional liability (CPL) coverage or a project-specific professional liability policy. This gap is commonly missed.

Certificate of Insurance (COI) Requirements

Every party on a commercial project will require certificates of insurance — ACORD 25 is the standard form — from every other party before work begins. What to verify on a COI:

• • Policy dates: Coverage must be in force during the project, not expired
• • Coverage amounts: Limits must meet contract minimums
• • Additional insured: Your entity must be named (verify the actual endorsement, not just the certificate)
• • Waiver of subrogation: Contract often requires the insurer to waive subrogation rights against specified parties
• • 30-day cancellation notice: Insurer must notify you if the policy is cancelled
• • Correct named insured: The entity on the policy must match the contracting entity

How Project Scope Defines Insurance Risk

Insurance premiums and required limits are fundamentally driven by your risk exposure — and your risk exposure is defined by your project scope. Before finalizing insurance for a project, the drawings and specifications tell you:

• • Project value — drives builder's risk coverage amount and GL aggregate adequacy
• • Occupancy type — hospitals, schools, and high-rise residential carry different risk profiles than office fit-outs
• • Special hazards — demolition, deep excavation, work on existing structures, hazardous materials abatement all require specific endorsements or separate policies
• • Design responsibility — any design-build scope triggers professional liability requirements the standard CGL doesn't address
• • Adjacent property exposure — excavation next to occupied buildings, work below grade near utilities — all affect GL limits adequacy

A plan review that identifies hazardous conditions, unusual scope, and design elements before bid is also a risk identification exercise — and risk identification is the first step in ensuring your insurance program is actually sized for the project you're building.