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    Base Infrastructure Schemas (BIS)

    Guide

    • Introduction

      • Overview
      • Federated Digital Twins
      • Modeling with BIS
      • Organization of BIS
      • Fabric of the Universe

    • Fundamentals

      • Element Fundamentals
      • Codes
      • FederationGuids
      • ElementAspect Fundamentals
      • Properties: Guidelines
      • Mixins
      • Model Fundamentals
      • Relationship Fundamentals
      • Schemas (“Domains”)
      • Classifying Elements
      • Type Definitions
      • Categories

    • Data Organization

      • Information Hierarchy
      • Modeling Perspectives
      • Top of the World
      • Single Responsible-Party Principle
      • Organizing Models and Elements
      • Spatial Composition
      • Modeling Systems
      • Organizing Definition Elements

    • Physical Modeling Perspective

      • 3D Guidance
      • PhysicalModel Hierarchy
      • Physical Models and Elements
      • Physical Materials
      • Quantity Takeoffs: Guidelines

    • Other Modeling Perspectives

      • Functional Models and Elements
      • Analysis Models and Elements
      • Information Models and Elements

    • Schema Evolution

      • Schema Customization
      • Data Evolution Across Time
      • Schema Versioning
      • Schema Production Status
      • Schema Design Guidelines

    • BIS Naming Guidelines

      • Rules and Recommendations
      • Special Terms
      • Summary of Exceptions
      • Abbreviations and Acronyms
      • Relationship “Strengths”

    • Other topics

      • BIS Schema Units
      • BIS Schema KindOfQuantities
      • BIS Schema Validation

    • References

      • BIS Glossary
      • Class-diagram Conventions
      • Instance-diagram Conventions

    Domain Schemas

    • Core domains

      • Overview
      • Analytical
      • BisCore
      • - Drawings & Sheets
      • - Provenance in BIS
      • Functional
      • Generic
      • PhysicalMaterial

    • Common domains

      • Overview
      • AECUnits
      • ClassificationSystems
      • DistributionSystems
      • DocumentMetadata
      • Linear Referencing
      • Profiles
      • SpatialComposition

    • Discipline-Physical domains

      • Overview
      • Building domains
      • Civil domains
      • Construction
      • Earthwork
      • Structural domains
      • Terrain

    • Discipline-Other domains

      • Overview
      • Structural domains

    • Standard schemas

      • Overview
      • BisCustomAttributes
      • CoreCustomAttributes
      • ECDbMap
      • Formats
      • Units

    Engineering Content (EC)

    • Overview
    • ECSchema
    • ECClass
    • ECEntityClass
    • ECMixinClass
    • ECStructClass
    • ECCustomAttributeClass
    • ECRelationshipClass
    • ECProperty
    • ECCustomAttributes
    • ECEnumeration
    • KindOfQuantity
    • PropertyCategory
    • PrimitiveTypes
    • CustomAttribute Container Types
    • Unit
    • Constant
    • Phenomenon
    • UnitSystem
    • Format
    • ECName
    • Changes Between ECObjects 2 and 3
Base Infrastructure Schema › Guide › Fundamentals
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BIS Guide - Fundamentals

  • Element Fundamentals
  • Codes
  • FederationGuids
  • ElementAspect Fundamentals
  • Properties: Guidelines
  • Mixins
  • Model Fundamentals
  • Relationship Fundamentals
  • Schemas ("Domains")
  • Classifying Elements
  • Type Definitions
  • Categories

Last Updated: 08 May, 2026

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  • BIS Guide - Fundamentals
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