What are MasterFormat numbers and titles?

MasterFormat is the most widely used classification system in the North American construction industry—the standard language for organizing construction specifications, cost codes, and project documentation.

What MasterFormat Is

MasterFormat organizes construction information by work results—the products, materials, and activities that go into building construction. It uses a six-digit numbering system organized into 50 divisions (Divisions 00 through 49), with each division covering a specific area of construction work:

• Division 00 — Procurement and Contracting Requirements
• Divisions 01 — General Requirements
• Divisions 02–14 — Facility Construction (sitework, concrete, masonry, metals, wood, thermal/moisture, openings, finishes, specialties, equipment, furnishings, special construction, conveying equipment)
• Divisions 21–28 — Facility Services (fire suppression, plumbing, HVAC, integrated automation, electrical, communications, electronic safety/security)
• Divisions 31–35 — Site and Infrastructure (earthwork, exterior improvements, utilities, transportation, waterway/marine)
• Divisions 40–49 — Process Equipment

The Numbering System

MasterFormat section numbers use a six-digit format (XX XX XX) that provides increasing specificity:

• Level 1 (XX 00 00) — Division level (e.g., 03 00 00 – Concrete)
• Level 2 (XX XX 00) — Group level (e.g., 03 30 00 – Cast-in-Place Concrete)
• Level 3 (XX XX XX) — Section level (e.g., 03 31 00 – Structural Concrete)
• Level 4+ — Further detail through decimal extensions

How MasterFormat Is Used

MasterFormat is the organizational backbone for:

• Specifications — Project manuals organize specification sections by MasterFormat numbers.
• Cost codes — Job cost systems map costs to MasterFormat sections for budgeting and benchmarking.
• Submittals — Submittal logs track product approvals by specification section.
• Bid packages — Procurement documents scope trade packages by MasterFormat divisions and sections.
• Keynote tables — Drawing annotations reference MasterFormat sections in BIM and CAD tools.
• RFI logs — Requests for information are tagged to the relevant specification section.

MasterFormat in CSI Dynamic Standards

CSI Dynamic Standards combines MasterFormat, UniFormat, and OmniClass into one accessible, efficient, and always-current digital edition. The Construction Standard is authorized by CSI to provide access for today's digital workflows. With CSI Dynamic Standards, your firm gets:

• Every MasterFormat number and title, always current
• Edition tracking to compare current and previous editions
• Governed crosswalks to UniFormat and OmniClass
• Searchable, browsable access through the Standards Tree and Navigator
• Firm-wide access under one subscription based on company type and revenue range