Definition
CSI MasterFormat is an industry-standard numbering system for organizing construction specifications and cost data (e.g., 01 00 00 General Requirements, 03 00 00 Concrete). Custom cost codes are codes your company defines (e.g., “DECK-LABOR,” “MAT-LUMBER”). Choosing between them affects consistency, training, and compatibility with GCs and owners.
Why It Matters
Many commercial and public projects require CSI or similar standards for bids and pay applications. Using CSI from the start makes it easier to work with GCs and meet contract requirements. Smaller or residential contractors often use simpler custom codes; the tradeoff is less portability but easier adoption.
Field Example
A sub bidding on a school project receives a schedule of values in CSI format (e.g., 08 41 00 Entrances and Storefronts). They map their internal “Doors & Frames” cost code to 08 41 00 for the application. A custom-only shop would need to build that mapping or adopt CSI for that job.
Calculation / Formula (if applicable)
Not applicable. This is a classification and organizational choice, not a calculation.
Software Application
Support both CSI MasterFormat (or a subset) and user-defined custom codes. Allow mapping custom codes to CSI for specific projects or exports. Provide templates or import for common CSI divisions so contractors can start standardized without building from scratch.
Tooltip Version
CSI is an industry-standard set of cost codes; custom codes are ones you define. Many GCs require CSI for reporting—software can support both and map between them.
Related Objects
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