- MasterFormat is the standard system for organizing construction specifications and cost information in the USA and Canada.
- It has 50 division numbers, from 00 to 49. Several numbers are reserved for future use.
- Sections use six-digit numbers, such as 09 29 00 for gypsum board, that move from broad to specific.
- Estimators use the same divisions to organize bids, so scope can be checked against the specifications line by line.
If you have opened a project manual or a commercial estimate, you have seen MasterFormat. It is the numbering system that puts concrete in Division 03, finishes in Division 09 and electrical in Division 26. This guide lists every division, explains how the numbering works and shows how estimators use MasterFormat to build bids that match the specifications.
What Is CSI MasterFormat?
MasterFormat is a standard for organizing construction information, published by the Construction Specifications Institute (CSI) in the USA and Construction Specifications Canada (CSC). It gives every type of work a fixed place and number, so architects, engineers, contractors, suppliers and estimators all refer to the same work in the same way.
It is used to organize project specifications, cost estimates, bid packages, product data and project records. Because everyone uses the same structure, a contractor can match a line in the estimate to the exact section of the specification that describes the work.
From 16 Divisions to 50
For many years MasterFormat had 16 divisions, and older estimators still remember mechanical work in Division 15 and electrical work in Division 16. In 2004, CSI and CSC expanded MasterFormat to 50 divisions to make room for building systems, site work and process equipment that had outgrown the old structure. Today, mechanical work is split into Divisions 21, 22 and 23, and electrical work into Divisions 26, 27 and 28.
Complete CSI MasterFormat Divisions List
The divisions are grouped into a procurement and contracting group (Division 00) and a specifications group, which is split into general requirements, facility construction, facility services, site and infrastructure, and process equipment.
| Division | Title | What it covers |
|---|---|---|
| 00 | Procurement and Contracting Requirements | Bid forms, instructions to bidders, contracts, bonds and conditions of the contract |
| 01 | General Requirements | Project administration, temporary facilities, quality requirements and closeout |
| 02 | Existing Conditions | Surveys, demolition, abatement and site remediation |
| 03 | Concrete | Formwork, reinforcing, cast-in-place and precast concrete |
| 04 | Masonry | Brick, concrete block, stone and mortar |
| 05 | Metals | Structural steel, steel joists, metal deck and miscellaneous metals |
| 06 | Wood, Plastics, and Composites | Rough carpentry, finish carpentry and architectural woodwork |
| 07 | Thermal and Moisture Protection | Waterproofing, insulation, roofing, flashing, joint sealants and fireproofing |
| 08 | Openings | Doors, frames, windows, storefronts, curtain wall, hardware and glazing |
| 09 | Finishes | Gypsum board, tile, ceilings, flooring, painting and wall coverings |
| 10 | Specialties | Toilet partitions, signage, lockers, fire extinguishers and accessories |
| 11 | Equipment | Kitchen, laboratory, athletic, residential and other equipment |
| 12 | Furnishings | Casework, countertops, window treatments and furniture |
| 13 | Special Construction | Pre-engineered structures, pools and special purpose rooms |
| 14 | Conveying Equipment | Elevators, escalators, lifts and dumbwaiters |
| 15 to 20 | Reserved | Reserved for future expansion |
| 21 | Fire Suppression | Sprinkler systems, standpipes and fire pumps |
| 22 | Plumbing | Piping, fixtures, water heaters and plumbing equipment |
| 23 | Heating, Ventilating, and Air Conditioning (HVAC) | Ductwork, HVAC equipment, piping, air distribution and controls |
| 24 | Reserved | Reserved for future expansion |
| 25 | Integrated Automation | Integrated building automation and control networks |
| 26 | Electrical | Power distribution, wiring, lighting and electrical equipment |
| 27 | Communications | Data, voice, audio-visual and structured cabling |
| 28 | Electronic Safety and Security | Fire alarm, access control, intrusion detection and video surveillance |
| 29 to 30 | Reserved | Reserved for future expansion |
| 31 | Earthwork | Site clearing, grading, excavation, fill and soil stabilization |
| 32 | Exterior Improvements | Paving, curbs, fencing, landscaping and irrigation |
| 33 | Utilities | Water, sanitary sewer, storm drainage and site power utilities |
| 34 | Transportation | Rail, roadway and airfield construction |
| 35 | Waterway and Marine Construction | Docks, dredging, seawalls and marine structures |
| 36 to 39 | Reserved | Reserved for future expansion |
| 40 | Process Interconnections | Process piping and interconnections between process equipment |
| 41 | Material Processing and Handling Equipment | Conveyors, cranes, hoists and material handling |
| 42 | Process Heating, Cooling, and Drying Equipment | Industrial heating, cooling and drying equipment |
| 43 | Process Gas and Liquid Handling, Purification, and Storage Equipment | Pumps, compressors, tanks and treatment equipment |
| 44 | Pollution and Waste Control Equipment | Air pollution control and waste handling equipment |
| 45 | Industry-Specific Manufacturing Equipment | Equipment for specific manufacturing industries |
| 46 | Water and Wastewater Equipment | Treatment equipment for water and wastewater plants |
| 47 | Reserved | Reserved for future expansion |
| 48 | Electrical Power Generation | Power generation equipment, such as solar, wind and generators |
| 49 | Reserved | Reserved for future expansion |
How Many Divisions Are in MasterFormat?
MasterFormat has 50 division numbers, from 00 to 49. Some numbers, such as 15 to 20, 24, 29, 30, 36 to 39, 47 and 49, are reserved for future use and contain no sections. That is why you may see MasterFormat described as having 50 divisions, even though fewer are in active use.
How MasterFormat Section Numbers Work
Each section has a six-digit number written in three pairs. The first pair is the division, the second pair is the broad subject within that division and the third pair narrows it further. Numbers can extend with a decimal for even more detail.
| Number | Level | Example |
|---|---|---|
| 09 | Division | Finishes |
| 09 20 00 | Level 2 | Plaster and Gypsum Board |
| 09 29 00 | Level 3 | Gypsum Board |
| 03 30 00 | Level 2 | Cast-in-Place Concrete |
| 26 05 19 | Level 3 | Low-Voltage Electrical Power Conductors and Cables |
Sections ending in 05 often cover common work results for that division, such as hangers, supports and identification that apply to many systems.
How Estimators Use MasterFormat
- Organizing the estimate: commercial estimates are usually broken into the same divisions as the specifications, so the owner and design team can follow them.
- Checking scope: reading the specification section by section helps catch work that is written but not drawn, such as testing, mock-ups or attic stock.
- Bid packages: general contractors split work into subcontract packages by division or section, which makes it easier to compare subcontractor quotes.
- Cost history: keeping past costs by division makes it easier to build budgets and check new estimates.
- Change orders: pricing changes by section keeps the change linked to the right specification and contract value.
Not every estimate follows MasterFormat. Subcontractors often organize by their own trade breakdown, and homebuilders may organize by construction phase. At Nextron Estimating, we prepare estimates by CSI division or trade by trade, depending on what the client needs. See how a division-based estimate looks in our sample estimates.
MasterFormat vs UniFormat
MasterFormat organizes information by work results and products, such as concrete, gypsum board or plumbing fixtures. UniFormat organizes information by building elements or systems, such as foundations, exterior walls or roofing. UniFormat is often used for early design-stage estimates, when systems are known but specific products are not. MasterFormat is used for construction documents and detailed bid estimates.
| MasterFormat | UniFormat | |
|---|---|---|
| Organized by | Work results and products | Building elements and systems |
| Typical use | Specifications and bid estimates | Early budgets and design-stage estimates |
| Example | 09 29 00 Gypsum Board | B2010 Exterior Walls |
| Best stage | Construction documents | Concept and schematic design |
Divisions Most Contractors Work In
On a typical commercial building, most of the cost falls in a handful of divisions: 03 Concrete, 05 Metals, 07 Thermal and Moisture Protection, 08 Openings, 09 Finishes, 21 to 23 for fire protection, plumbing and HVAC, 26 Electrical and 31 to 33 for site work. Each of these has its own estimating methods and common mistakes. Our trade guides explain them in detail, for example concrete estimating, drywall estimating and electrical estimating.
Frequently Asked Questions
What are the CSI MasterFormat divisions?
They are the 50 numbered categories, from 00 to 49, that organize construction specifications and cost information, such as 03 Concrete, 09 Finishes, 23 HVAC and 26 Electrical.
How many CSI divisions are there?
MasterFormat has 50 division numbers, from 00 to 49. Several are reserved for future use, so fewer are active.
What happened to the old 16 CSI divisions?
MasterFormat had 16 divisions until 2004, when it was expanded to 50. Old Division 15 Mechanical and Division 16 Electrical were split into Divisions 21 to 23 and 26 to 28.
What is Division 01 in construction?
Division 01 General Requirements covers project administration, temporary facilities, quality requirements, submittals and closeout that apply to the whole project.
What division is drywall in?
Gypsum board is in Division 09 Finishes, in section 09 29 00 Gypsum Board, with assemblies covered under related Division 09 sections.
What division is HVAC?
HVAC is Division 23. Fire suppression is Division 21 and plumbing is Division 22.
What division is electrical?
Electrical is Division 26. Communications is Division 27, and electronic safety and security, including fire alarm, is Division 28.
Who publishes MasterFormat?
MasterFormat is published by the Construction Specifications Institute (CSI) and Construction Specifications Canada (CSC).
What is the difference between MasterFormat and UniFormat?
MasterFormat is organized by work results and products and is used for specifications and bid estimates. UniFormat is organized by building systems and is often used for early budgets.
Do all estimates follow MasterFormat?
No. Commercial estimates usually do, but subcontractors often use a trade breakdown and homebuilders may organize by phase. We can prepare estimates either way.
Related Guides and Services
- Construction estimating software: how to choose
- Commercial construction cost estimating
- Sample estimates organized by CSI division
- Sample construction cost estimate guide
- Quantity takeoff services
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