Scheme

Technical Specification

BDS is formally defined by an XML Schema (XSD) version 1.0. The key components of the schema include:

BDS (Root Element)

Defines the overall document structure:

• Attributes: Version (required), Name (optional)

• Elements:

• <Description>

• <FileVersion>
• <ScheduleSets>: collection of <ScheduleSet>
• <ResponsibleParty>

ScheduleSet

Groups multiple schedules:

• Attributes: Name
• Optional elements: <Description>, <Group>, <Discipline>
• Contains: one or more <Schedule> elements

Schedule

Defines one schedule template:

• Attributes: Name

• Contains:

• <Description> (optional text)

• <IfcClasses>: list of applicable IFC types
• <Fields>: one or more PropertyField or AttributeField
• <Filters>: optional list of filter conditions
• <Sort>: optional list of sort conditions
• <Group>: optional field grouping definition

PropertyField

Defines a schedule column from an IFC property:

<PropertyField Id="DoorWidth">
  <PropertySetName>Dimensions</PropertySetName>
  <PropertyName>Width</PropertyName>
</PropertyField>

AttributeField

Defines a column from an IFC attribute:

<AttributeField Id="DoorName">
  <Attribute>ObjectName</Attribute>
</AttributeField>

Filter

Defines a conditional rule:

<Filter>
  <Field>DoorWidth</Field>
  <Operator>GreaterThan</Operator>
  <Value>0.8</Value>
</Filter>

Sort

Defines how to order rows:

<Sort>
  <Field>DoorName</Field>
  <Order>Ascending</Order>
</Sort>

Example Structure

<BDS Name="ExampleSchedules" Version="1.0">
  <Description>Standard schedules for Project X</Description>
  <FileVersion>1.0.0</FileVersion>
  <ScheduleSets>
    <ScheduleSet Name="General">
      <Discipline>Architectural</Discipline>
      <Schedules>
        <Schedule Name="DoorSchedule">
          <IfcClasses>
            <IfcClass>IfcDoor</IfcClass>
          </IfcClasses>
          <Fields>
            <PropertyField Id="DoorWidth">
              <PropertySetName>Dimensions</PropertySetName>
              <PropertyName>Width</PropertyName>
            </PropertyField>
            <AttributeField Id="DoorName">
              <Attribute>ObjectName</Attribute>
            </AttributeField>
          </Fields>
          <Filters>
            <Condition>
              <Field>DoorWidth</Field>
              <Operator>GreaterThan</Operator>
              <Value>0.8</Value>
            </Condition>
          </Filters>
          <Sort>
            <Condition>
              <Field>DoorName</Field>
              <Order>Ascending</Order>
            </Condition>
          </Sort>
        </Schedule>
      </Schedules>
    </ScheduleSet>
  </ScheduleSets>
  <ResponsibleParty>Acme BIM Team</ResponsibleParty>
</BDS>

This structure enables software tools to interpret and apply standard data queries across different BIM environments, ensuring consistency, repeatability, and collaboration.