What Is CSI MasterFormat? Divisions and Section Numbers

The first pair of digits is the division. The next pairs narrow the work result. 03 is concrete. 03 30 00 is cast-in-place concrete. A level 4 number such as 03 30 53, miscellaneous cast-in-place concrete, is more specific still. You do not need to memorize the list to use a project manual. You need to know that the number on the submittal stamp should exist in the table of contents.

Within a section, the three-part format is the usual structure: Part 1 General, Part 2 Products, Part 3 Execution. Submittals, quality assurance, and warranties live in Part 1. The product the contractor wants to substitute is judged against Part 2. Installation and field quality control live in Part 3. A review that only reads the product name misses the execution requirements.

Division 01 is where submittal procedures, substitution procedures, quality requirements, temporary facilities, and closeout requirements are written once. Technical sections then point back to them. A contractor who prices only Divisions 02 through 48 and treats Division 01 as boilerplate will miss cost. A reviewer who approves a submittal without the Division 01 submittal procedure will miss process.

General conditions of the contract, often AIA A201, are not Division 01. They are usually bound in Division 00 or incorporated by reference. Division 01 is the specifier’s administrative specifications. The general conditions are the contract’s legal machine. Both apply. They are written by different authors.

Division 00 is procurement and contracting requirements, and Division 01 is general requirements. Facility Construction runs from 02 Existing Conditions, 03 Concrete, 04 Masonry, 05 Metals, 06 Wood, Plastics, and Composites, 07 Thermal and Moisture Protection, 08 Openings, 09 Finishes, 10 Specialties, 11 Equipment, 12 Furnishings, and 13 Special Construction through 14 Conveying Equipment. Divisions 15 through 19 are reserved.

Facility Services holds 21 Fire Suppression, 22 Plumbing, 23 Heating, Ventilating, and Air Conditioning, 25 Integrated Automation, 26 Electrical, 27 Communications, and 28 Electronic Safety and Security. Site and Infrastructure holds 31 Earthwork, 32 Exterior Improvements, 33 Utilities, 34 Transportation, and 35 Waterway and Marine Construction. Process Equipment, Divisions 40 through 48, covers industrial and plant work and is rarely used on a building project.

Before the 2004 edition, MasterFormat used 16 divisions. Division 02 was Site Work, mechanical was Division 15, and electrical was Division 16. A set of drawings or a specification written in that format cites numbers that do not match the current table, and a five-digit section number is the giveaway.

The practical risk is on renovation and addition work. An existing project manual in the old format sits next to a new one in the current format, and a cross-reference from one to the other points at the wrong trade unless somebody maps them. Check which edition a section number belongs to before filing a submittal against it.

Concrete is Division 03, masonry 04, metals 05, wood 06, thermal and moisture protection 07, openings 08, finishes 09. Fire suppression is 21, plumbing 22, HVAC 23, electrical 26. Site work is in the 31 through 33 range: earthwork, exterior improvements, utilities. If a drawing says "see specs" with no number, MasterFormat at least tells you which division the requirement should have lived in.

Specifiers add project-specific sections and delete unused ones. A short project manual is not a violation. A project manual that invents a private numbering scheme, or that cites a section it does not contain, breaks the cross-references on the drawings. The drawing note and the section number have to match.

UniFormat organizes information by elements and systems, such as substructure, shell, and services, which matches how early estimates and BIM assemblies are discussed. MasterFormat organizes by work results and products, which matches how the work is bought and installed. A DD estimate in UniFormat and a CD project manual in MasterFormat are supposed to describe the same building. They will not line up row for row.

Switching systems midstream without a crosswalk is how scope falls out of the estimate. If the owner’s cost report is in UniFormat and the spec is in MasterFormat, someone has to own the map. The numbers are standards. The map is a project decision.