CSI MasterFormat

The industry-standard classification system for organizing construction cost data into divisions and sections.

CSI MasterFormat is the dominant classification system for construction specifications and cost coding in North America, maintained by the Construction Specifications Institute.

It organizes work into 50 numbered divisions, each containing sections for specific scope items.

Division 03 — Concrete: cast-in-place, precast, finishing, decorative Division 31 — Earthwork: site clearing, excavation, fills, soil treatment Division 32 — Exterior Improvements: site concrete, paving, curbs Division 33 — Utilities: water, sewer, storm — concrete encasements

GCs, owners, and architects organize specifications by CSI section. If your bid is structured by CSI codes, you can trace every line in your estimate back to a section in the spec book. Disputes get easier. Change orders get cleaner.

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