Understanding CSI MasterFormat Divisions for Estimating
MasterFormat gives estimators, designers and contractors a shared structure for organizing scope. Here is how the divisions work and how to use them in an estimate.
What MasterFormat is
MasterFormat is a standard published by the Construction Specifications Institute (CSI) and Construction Specifications Canada for organizing construction specifications and related information. It groups work into numbered divisions, each with sections identified by a six-digit number, such as 03 30 00 for cast-in-place concrete.
Because specifications are usually organized with MasterFormat, using the same structure for an estimate makes it easy to connect each cost back to the specification section that defines the requirements.
How the divisions are grouped
The current edition organizes divisions into subgroups. Division 00 covers procurement and contracting requirements and Division 01 covers general requirements. The facility construction subgroup runs from Division 02, Existing Conditions, through Division 14, Conveying Equipment.
Facility services include fire suppression, plumbing, HVAC, electrical, communications and electronic safety and security, numbered Divisions 21 through 28. Site and infrastructure work falls in Divisions 31 through 35, and process equipment is in Divisions 40 through 48. Some numbers are reserved for future use, so the sequence is not continuous.
- Division 03: Concrete
- Division 04: Masonry
- Division 05: Metals
- Division 06: Wood, Plastics and Composites
- Division 07: Thermal and Moisture Protection
- Division 08: Openings
- Division 09: Finishes
- Divisions 22, 23 and 26: Plumbing, HVAC and Electrical
- Divisions 31 and 32: Earthwork and Exterior Improvements
Reading a section number
A MasterFormat number has three pairs of digits. The first pair is the division, the second identifies a broad area within that division, and the third identifies a more specific section. For example, 09 21 16 refers to gypsum board assemblies within Division 09, Finishes.
Some projects add a decimal extension for even more detail. In an estimate, you can work at whatever level is useful. A budget might summarize by division, while a detailed bid estimate tracks individual sections.
Using MasterFormat in an estimate
Organizing an estimate by division makes it easier to compare against the project manual, line up subcontractor bids with the right scope and compare costs across projects. It also helps owners and lenders review the estimate in a familiar format.
MasterFormat does not decide who performs the work. A single subcontractor might cover several sections across divisions, and one section might be split among trades. A good estimate uses MasterFormat as a reference while keeping a separate view by bid package when needed.
MasterFormat and UniFormat
UniFormat, another CSI standard, organizes information by building element, such as substructure, shell and interiors, rather than by material or work result. It is often used for early conceptual estimates, before specifications are written.
Many projects use UniFormat in early design and move to MasterFormat as construction documents develop. Estimates that can be mapped between the two make it easier to compare budgets across phases.