Promotion and Exclusion Settings in the open BIM Module

Why Model Hierarchy Matters for Quantity Extraction

IFC files organise elements in a tree: each element can contain one or more child elements nested beneath it. In a structural model, for example, a column assembly might be the parent element, with its concrete body and embedded reinforcement as children. In a road model, a carriageway object might contain separate child elements for each road layer.

By default, the open BIM Module extracts quantities from the lowest level of this hierarchy: the individual child elements. In many models, this is exactly what you want. Each child holds its own volume or area, and the module can read and group them directly.

However, two common situations require a different approach:

• The child elements do not carry quantity properties. The quantities exist only on the parent element, and the children are geometric sub-components with no measurable data of their own.
• Some elements are irrelevant to the assessment, such as fixings, labels, or guardrail components that have geometry but should not be included in the material quantities.

The Promotion and Exclusion settings in the open BIM Module give you direct control over both situations.

Excluding Unwanted  Elements

Exclusion removes specific elements from the quantity extraction entirely. The excluded elements remain visible in the 3D viewer, but they do not appear as rows in the Quantity Table and do not contribute quantities to the assessment.

To exclude elements, enter one or more dbIds in the Exclusion field, separated by commas. Any element which has its id inside this list , is excluded from quantity extraction. You can have access to the ids of the elements from the Data Grid

WHEN TO USE EXCLUSION

Exclusion is the right choice when elements are present in the model but are not relevant to the material assessment. Common examples include:

• Guardrail posts, bolts, or fixings that have geometry but a negligible material contribution
• Drainage grates or covers that are modelled as children of a pipe or channel element
• Annotation or reference objects that were exported into the IFC by the authoring tool
• Duplicate representations of an element that appear at multiple levels of the hierarchy

Promoting Parent Elements

Promotion tells ORIS to read quantities from a parent element rather than from its children. When a parent element is promoted, its own property sets are used for quantity extraction, and its children are bypassed entirely.

This is needed when the parent holds all the useful data, such as total volume or a material property, and the children are purely geometric sub-components with no quantity properties of their own. Attempting to extract from the children in this case returns empty or zero values, producing a Quantity Table with rows that cannot be mapped.

WHEN TO USE PROMOTION

Promotion is appropriate when:

• The model was authored so that quantities are stored on a parent assembly object, and the child objects represent individual pieces or sub-elements without their own quantity properties.
• The Model Browser shows child elements, but inspecting their property sets (via right-click, Show Properties) reveals no volume, area, or length value.
• A green circle is not achievable on the child rows in the Quantity Table even after selecting the correct property, because the property is genuinely absent from those elements.

Applying Promotion and Exclusion: Step by Step

The steps below apply to any model where the default quantity extraction returns incomplete or incorrect results due to the parent-child structure.

Promotion vs Exclusion: Choosing the Right Approach

Both settings modify the default quantity extraction behaviour, but they address different problems. Use the table below to identify which one applies to your situation.

A Note on Model Quality

Promotion and Exclusion settings are designed to handle the most common IFC export scenarios, where the hierarchy does not perfectly align with what the assessment needs. They are not a substitute for a well-prepared model.

If your model requires extensive use of both promotion and exclusion across many element types, it may be worth reviewing the export settings in the authoring tool. Adjusting which property sets are exported, or how the hierarchy is structured at export, can reduce the configuration work needed in ORIS and produce a more reliable quantity extraction with less manual intervention.