MasterFormat Division 31: Earthwork

MasterFormat Division 31 organizes the specification sections, cost codes, and work results for earthwork across the construction industry. As part of CSI's consensus-based classification system, Division 31 provides the authoritative structure that specifiers, estimators, contractors, and software platforms use to organize earthwork work.

Division 31 covers site earthwork—clearing, grading, excavation, fill, soil stabilization, and erosion control that prepare the ground for construction.

This division includes site clearing, earth moving, earthwork methods, shoring and underpinning, tunneling and mining, and soil treatment.

Division 31 contains multiple levels of sections and subsections that organize this scope into a precise, consensus-based hierarchy. These sections provide the numbering backbone for project manuals, bid packages, cost databases, and BIM models. When teams reference Division 31 consistently, every document from concept estimate to closeout speaks the same language.

Licensed through The Construction Standard, CSI Dynamic Standards includes the authoritative, always-current section numbers and titles for Division 31—searchable, cross-referenced, and edition-aware.

Common Division 31 Work Results

Common Division 31 work results include Site Clearing, Earth Moving, Excavation and Fill, Erosion and Sedimentation Controls, Earthwork Methods, Shoring and Underpinning. These examples help teams orient the division, but they are not a substitute for current licensed standards access. MasterFormat section titles, numbering depth, and coordination notes can change as CSI updates the standard. For production specifications, estimating templates, cost databases, procurement workflows, or software integrations, teams should validate every Division 31 reference against CSI Dynamic Standards.

• 31 10 00 – Site Clearing
• 31 20 00 – Earth Moving
• 31 23 00 – Excavation and Fill
• 31 25 00 – Erosion and Sedimentation Controls
• 31 30 00 – Earthwork Methods
• 31 40 00 – Shoring and Underpinning

• Civil engineers designing site grading
• Earthwork and excavation contractors
• Geotechnical engineers specifying soil treatment
• Environmental engineers managing erosion control

Whether you write specifications, estimate costs, coordinate BIM models, or build software that references earthwork, Division 31 numbers and titles are the shared vocabulary your work depends on.

Why Division 31 Matters in Project Delivery

Division 31 is used wherever teams need a stable reference for scope, responsibility, and deliverables. Designers use it to organize specifications. Estimators use it to structure takeoffs and cost assemblies. Contractors use it to align bids, submittals, RFIs, and closeout documents. Owners and facility teams use it to keep project records searchable after turnover.

When Division 31 is out of date, copied from an old PDF, or mixed with local aliases, coordination breaks down quickly. A section number in a project manual may not match a cost code in an estimate. A BIM object may point to a stale classification. A procurement package may separate work differently than the specification. Current, licensed MasterFormat access reduces those mismatches by keeping every team aligned to the same controlled source.

How Division 31 Connects to Other Standards

UniFormat

Division 31 maps to UniFormat G (Sitework)—the site preparation work that precedes building construction.

OmniClass

OmniClass Table 22 (Work Results) includes earthwork results; Table 13 (Spaces by Function) covers site spaces.

These cross-references are maintained by CSI through governed crosswalks—not assembled ad hoc by individual project teams. Through The Construction Standard, licensed access to CSI Dynamic Standards gives teams these relationships so they can navigate between specifications, elements, and lifecycle categories without manual remapping.

Related MasterFormat and Classification Lookups

Division 31 is part of the broader MasterFormat system and should be read alongside related CSI standards. MasterFormat organizes work results for specifications and procurement. UniFormat organizes building elements for early estimating and conceptual planning. OmniClass extends classification across spaces, products, activities, phases, and information used through the facility lifecycle.

Use Division 31 pages as an orientation point, then move into the current CSI Dynamic Standards platform when a project, template, data model, or commercial product depends on authoritative numbers and titles. The Construction Standard is designed for that workflow: find the relevant division, understand the classification context, and access the current standard instead of relying on stale spreadsheet exports or uncontrolled copies.

Why Edition Awareness Matters

MasterFormat evolves through consensus-based updates. Projects that span multiple years may reference different editions. Division 31 sections may be added, renumbered, or revised between editions. Without edition awareness, teams risk referencing obsolete section numbers, creating specification conflicts, and generating RFIs that delay construction.

Licensed through The Construction Standard, CSI Dynamic Standards gives teams full edition context for Division 31—teams know which edition applies at each project milestone, what changed, and where those changes affect their work.

The Licensing Relationship

CSI—the Construction Specifications Institute—stewards Division 31 as part of MasterFormat. CSI Dynamic Standards includes MasterFormat, UniFormat, and OmniClass as a connected, edition-aware system. The Construction Standard provides licensed access to CSI Dynamic Standards:

• Always current: Section numbers and titles reflect the latest CSI-approved updates
• Edition-aware: Teams know which edition applies and what changed between releases
• Cross-referenced: Governed relationships to UniFormat and OmniClass stay maintained
• Integration-ready: Enterprise solutions carry Division 31 data into the tools you already use