Class Code 6258
Foundation Preparation Work
Class Code 6258 covers foundation preparation work — the site excavation, subgrade preparation, form setting and related tasks performed before concrete placement. The September 1, 2026 approved pure premium rate for this classification is $4.661 per $100 of payroll. Understanding this classification helps California employers correctly classify payroll, manage risk, and control workers' comp costs.
What Class Code 6258 Covers
This classification applies to operations that prepare building and structure foundations prior to concrete placement. Typical activities include clearing and grading the foundation area, excavation and trenching for footings, installation of formwork, placement and tying of rebar and embedments, compaction and proof-rolling of subgrade, placement of base materials (gravel, sand) and dewatering or pumping to maintain a dry work area. It covers hands-on crews and equipment operators who perform those tasks but generally stops at concrete placement and finishing (which are usually coded separately). Work done to stabilize or shore excavations, install temporary shoring or bracing, and perform non-structural backfill after inspection also falls under this code when part of foundation preparation.
Who It Applies To
- Commercial and residential general contractors performing footing and foundation prep crews
- Excavation and site-prep subcontractors who dig, grade, and compact foundation areas
- Form carpenters who build and set footing and foundation forms (prior to concrete pour)
- Rebar crews that place and tie reinforcement and install embedded anchor bolts
- Heavy equipment operators running excavators, skid steers, compactors, and pumps used for foundation prep
Common Job Duties
- Stripping and clearing vegetation and topsoil from the foundation footprint
- Excavating trenches and holes for footings and grade beams
- Installing and bracing timber or metal formwork for footings and foundation walls
- Placing, cutting and tying reinforcing steel and setting embeds and anchor bolts
- Compacting subgrade and base material with rollers, plate compactors or tampers
- Dewatering, pumping, and installing temporary drains to maintain dry excavations
- Backfilling and initial grading around foundations after inspections
Common Injury Risks
Understanding the $4.661 Rate
The approved pure premium of $4.661 per $100 of payroll represents the portion of premium intended to cover expected claim costs for this class. Insurers multiply that rate by your payroll (payroll/100) to get the base pure premium, then add expense loads, policy fees, state assessments and apply your experience modification, schedule credits, audits, and any deductible or retro programs to produce the final premium. Payroll classification accuracy, loss history, safety programs, subcontractor use, and claims management strongly influence the premium you ultimately pay.
Cal/OSHA Compliance Requirements
Cal/OSHA Construction Safety Orders require competent person oversight for excavations and trenches, protective systems (sloping, shoring or shielding), atmospheric testing in confined or deep excavations, and controls for falling objects and heavy equipment. Employers must maintain written site-specific excavation plans when conditions are complex, provide fall protection where needed, and ensure employee training and PPE consistent with Title 8 requirements and the competent person standard.
How Key HR Helps Employers Under Class Code 6258
A PEO like Key HR can reduce workers' comp costs for foundation-prep employers by auditing payroll classifications, consolidating coverage, and applying proven loss-control programs specific to excavation and formwork hazards. Key HR provides safety program templates, training (competent person trenching, confined space awareness), claims management and return-to-work coordination to shorten claim durations and protect experience modification rates.
Get a QuoteFrequently Asked Questions
How do I know if my crews should be coded to 6258 or another classification?
Use the actual job tasks: crews that perform excavation, subgrade prep, form setting, rebar placement and dewatering prior to concrete placement fit 6258. If your employees pour, finish or cure concrete, they may fall under a concrete placement/finishing code. Keep task-level payroll records and verify classifications with your insurer or PEO to avoid misclassification at audit.
Does foundation preparation include shoring and dewatering work?
Yes—temporary shoring, bracing and dewatering performed as part of preparing the foundation site are included in 6258 when they are integral to excavation and subgrade preparation. Permanent structural shoring or specialized tunneling operations may be classified differently; consult your underwriter for complex jobs.
What practical steps lower workers' comp costs for foundation prep crews?
Implement a competent-person program for excavations, enforce trench protective systems, provide task-specific training (equipment, rigging, rebar handling), use documented return-to-work policies, and maintain equipment inspection logs. Accurate payroll classification and proactive claims handling through a PEO or carrier also help preserve your experience modification and reduce premiums.
Quick Facts
- Class Code
- 6258
- Classification
- Foundation Preparation Work
- Pure Premium Rate
- $4.661 / $100 payroll
- Effective Date
- September 1, 2026
- Source
- WCIRB Approved Filing
Manage Workers' Comp Through a PEO
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