Modular construction speeds up project timelines and reduces waste, but the unique manufacturing and assembly process introduces distinct insurance needs that differ from traditional building. Understanding what coverage applies—and what doesn't—can save you thousands in unexpected costs and prevent project delays. Let's walk through the specific protections you need.
Why Modular Construction Insurance Is Different
Standard builders risk policies don't always account for factory-built modules, transportation between facilities, and stacking of prefabricated units on-site. Your insurance must cover the manufacturing phase at the plant, transit to the jobsite, and final assembly—three separate environments with different hazards. A cracked module discovered during transport or installation can halt your project; proper coverage ensures you're not absorbing that loss.
Key Coverage Types for Modular Projects
Builders Risk (Installation Floaters) This is your foundation. It protects modules from damage during storage, transportation, and installation, typically covering theft, weather, vandalism, and equipment breakdown. Premiums range from 0.5% to 1.5% of the total project value, depending on the module complexity and site location. Your broker should specify coverage for "in-transit" modules and on-site stacking areas.
Manufacturer's Liability If you're contracting directly with a modular manufacturer, confirm their product liability insurance covers defects in design, materials, or workmanship. Ask for a Certificate of Insurance naming you as an additional insured, and verify limits of at least $1–2 million for commercial projects. Many manufacturers carry $2–5 million in umbrella coverage.
General Liability Standard GL policies must explicitly include modular assembly and installation work. Some insurers exclude prefab work by default, so your agent needs to confirm coverage before you sign. Typical limits for modular projects range from $2 million general aggregate to $5 million for larger developments.
Property Damage Coverage Modules arriving damaged or defective is common—expect 2–5% of shipments to have minor issues. Your policy should cover repair or replacement of faulty units without requiring you to return them to the factory, since logistics costs can exceed repair expenses.
Transportation & Logistics Insurance
Modules travel by truck or rail, and delays from weather or accidents directly impact your project schedule. Ask your insurer whether they cover:
- Loss of rent or business interruption if a module arrival is delayed beyond a set number of days
- Cargo coverage for modules in transit (separate from builders risk)
- Liability for damage caused by your transport contractor to third-party property
Transportation premiums typically add $500–$2,000 per shipment for high-value modules. Bundling transportation under your main builders risk policy is often cheaper than separate cargo policies.
Claims Process for Modular Projects
Document Everything Before modules arrive, photograph the delivery truck, packaging, and surrounding area. Inspect each unit within 48 hours and photograph any damage, cracks, or cosmetic defects. File damage claims within 72 hours—insurance companies enforce strict notice timelines. Keep invoices, shipping manifests, and inspection reports.
Staged Inspections Modular projects suit phased claims. As units are installed and connected, photograph connection points, electrical hookups, and structural alignment. If issues emerge weeks into assembly, staged documentation proves when defects were introduced (manufacturer vs. installer).
Supply Chain Delays If a module is delayed, your business interruption rider (if included) may cover lost rental income or extended financing costs. Quantify this in writing before the project starts—typically 10–15% of the module's installed value per month.
Comparing Insurance Quotes
Request at least three quotes specifying:
- Project timeline: Duration of manufacturing, transport, and assembly phases
- Total insured value: Cost of all modules plus installation materials
- Site location and local hazards: Flood zones, high-wind areas, or earthquake regions increase premiums 20–40%
- Your experience: General contractors with 5+ modular projects typically get 10–15% rate reductions
Expect costs between $8,000–$25,000 for a medium residential or small commercial modular project. Larger developments (10+ modules) may negotiate volume discounts.
Mercoly makes it simple to compare trusted modular construction providers and their insurance credentials in one place—ensuring you work with firms that carry proper coverage before problems start.
Frequently Asked Questions
Q: Does my general liability insurance cover modular assembly on-site? Not automatically. Many GL policies exclude prefab installation unless explicitly endorsed; confirm coverage in writing before work begins.
Q: What happens if a module arrives damaged and the manufacturer disputes the claim? Your builders risk policy should pay for repairs or replacement without requiring you to litigate against the manufacturer—this is why "in-transit" coverage is critical.
Q: Can I reduce insurance costs by bundling modular and site work under one policy? Yes. Contractors who pair modular coverage with traditional builders risk on the same site often receive 15–20% discounts.
Compare modular providers with verified insurance coverage on Mercoly to protect your project from day one.