Skip to content

List (Multivalue)

In Revit, a list typically refers to a parameter that can hold multiple values — either as separate items (in the case of multi-value custom parameters), or as a single text string formatted like a list (e.g. comma- or semicolon-separated values).

For example, a Classification Tags parameter might list multiple entries like "Enclosure.Wall; FireResistance.60min". Rule checks can then verify whether required values are included or excluded. Lists are especially useful when an element belongs to multiple systems, zones, or classifications.

✅ Validator: List: In

Description: Checks that a value exists within a predefined list of allowed values.

🔧 Revit Example:

  • Parameter: Fire Rating of a Door Type
  • Rule: Fire Rating IN [30, 60, 90, 120]

📌 Use Case:

Ensures that all fire-rated doors are assigned standard, approved resistance values, helping with regulatory compliance, accurate scheduling, and coordination with fire safety consultants.

✅ Validator: List: Not In

Description: Checks that a value is not within a predefined list of disallowed values.

🔧 Revit Example:

  • Parameter: Material of a Wall Type
  • Rule: Material NOT IN ['Plasterboard', 'Unknown', 'Generic']

📌 Use Case:

Prevents the use of placeholder or non-approved materials in final design stages. Helps ensure that only validated, specification-compliant materials are used for procurement and documentation.

✅ Validator: List: Equals

Description: Checks that a list matches exactly — same items, same order (if relevant), and no extras.

🔧 Revit Example:

  • Parameter: Classification Codes of a Wall Type
  • Rule: Classification Codes = ['Element.Enclosure.Wall', 'FireResistance.60min']

📌 Use Case:

Ensures that classification codes are complete and exactly match required tags for data handover or classification systems like OmniClass or Uniformat. Helps ensure consistent exports and avoid missing metadata.

✅ Validator: List: Not Equal

Description: Checks that a list does not exactly match a specific list — catches incorrect or incomplete combinations.

🔧 Revit Example:

  • Parameter: Assigned Zones of a Mechanical Equipment Instance
  • Rule: Assigned Zones ≠ ['Zone A', 'Temporary']

📌 Use Case:

Prevents specific invalid combinations of zones — for example, making sure that equipment is not assigned to a temporary zone in final design. Helps maintain clean system zoning and avoids coordination mistakes.

✅ Validator: List: Any of the Words Are Contained in the List

Description: Passes if any of the specified words are found in the target list.

🔧 Revit Example:

  • Parameter: Material Tags of a Wall Type
  • Rule: Contains any of ['Asbestos', 'Lead', 'Hazardous']

📌 Use Case:

Identifies elements that contain potentially hazardous materials, even if multiple tags are present. Supports health and safety reviews, renovation risk analysis, or demolition planning.

✅ Validator: List: None of the Words Are Contained in the List

Description: Passes only if none of the specified words appear in the target list.

🔧 Revit Example:

  • Parameter: Material Tags of a Floor Type
  • Rule: Must not contain any of ['Deprecated', 'Generic', 'Placeholder']

📌 Use Case:

Ensures that no temporary or non-approved tags are left in the model before issuing for construction or export. Helps enforce clean, contract-ready data.