Workers' comp class code · Construction & Trades
Class code 5478 — Insulation Work
Installation of thermal or acoustic insulation in buildings.
This classification covers insulation contractors who install thermal or acoustic insulation in walls, attics, floors, and other building cavities. Work includes fitting batts of fiberglass or mineral wool insulation between framing members, spraying foam insulation using specialized equipment, and blowing loose-fill insulation into attics and closed cavities. Jobs happen at various stages of construction, often before drywall closes up the walls.
Payroll includes installers who fit batt insulation and operate spray foam or blown-in equipment, along with helpers who handle material staging and site prep such as covering surfaces that need protection from overspray. Spray foam crews typically work in small teams due to the specialized equipment and protective gear required.
Attic work in cramped, poorly ventilated spaces exposes installers to heat stress and awkward postures while maneuvering around trusses and ductwork. Fiberglass fibers cause skin and respiratory irritation with repeated contact, and spray foam chemicals require respiratory protection since the isocyanates involved can cause serious respiratory sensitization with poor ventilation or inadequate PPE.
What code 5478 typically includes
- Batt insulation installation in walls and floors
- Spray foam insulation application
- Blown-in loose-fill attic insulation
- Attic and crawlspace insulation work
- Vapor barrier and air sealing performed alongside insulation
Codes this one gets confused with
5445 — Wallboard/Drywall Installation
Insulation is installed inside the wall cavity before drywall closes it up, making these sequential but distinct trades on the same wall assembly.
See code 54455479 — Sheet Metal Work
Duct insulation wrap overlaps with sheet metal HVAC work in some cases, but general building insulation is a separate classification from ductwork fabrication.
See code 54795537 — HVAC Installation
HVAC contractors sometimes insulate ductwork directly, but whole-building insulation of walls and attics falls under the dedicated insulation classification.
See code 5537What this code means for your premium
Insulation work rates in the moderate range for construction trades, with confined attic space and chemical exposure from spray foam balancing out the general absence of height or heavy equipment hazards.
Estimate your premiumClassification is not final until a carrier assigns it. Code numbers, wording and exceptions vary by state and rating bureau — several states run their own bureaus. This page is general reference written in our own words; your carrier's underwriter assigns the code based on your actual operations and payroll records.
Questions about code 5478
Ready to see your options?
One application. Up to 10 competing quotes. Answer a few questions and we will shop your business to our A-rated carrier network, then a licensed agent walks you through the options.