BIM Linking
BIM linking is how you connect elements from your IFC model to items in the quantity table. It's the core workflow for BIM-based takeoffs in Sparkel — and understanding how it works is what separates fast, reliable takeoffs from frustrating ones.
Manual linking
Manual linking is straightforward:
Select the item in the quantity table you want to link elements to.
In the viewer, select the BIM elements you want to measure — click to select one, hold Shift to add more, or hold Ctrl/Cmd to box-select a group.
Click Link selected elements.
The item's quantity updates immediately based on the geometry of the linked elements.
To verify the link, click the item again. The linked elements highlight in the viewer. The number of linked elements is shown on the item row.
To unlink, select the item and the elements you want to remove, then click Unlink selected elements.
Dynamic linking
Dynamic linking lets you define a rule — based on BIM properties — that automatically links all matching elements to an item. This is significantly faster for large models where manually selecting every element isn't practical.
To set up a dynamic linking rule:
Select the item you want to link.
Open the dynamic linking panel for that item.
Define the filter — choose a property (e.g. IFC class, material name, floor level) and a value to match.
All elements matching the rule link automatically. The quantity updates in real time.
Dynamic links stay active — if the model is updated and new elements match the rule, they'll be included automatically.
What quantity does linking produce?
When you link an element, Sparkel reads the geometric quantity that matches the item's unit of measurement:
m³ — reads the element's volume
m² — reads the element's surface area or net face area
m — reads the element's length
pcs — counts the number of linked elements
You can also use dynamic quantities to calculate a custom expression based on BIM properties — for example, deriving weight from volume using a material density factor. See The Quantity Table for how to configure dynamic quantity formulas on an item.
Inspecting BIM properties
Before setting up dynamic linking rules, click any element in the viewer to see its full property set. This shows you what properties are available, what values they contain, and whether they're consistent across elements of the same type. This inspection step is worth doing upfront — it tells you whether dynamic linking will work cleanly or whether you'll need to supplement with manual selection or shapes.
Colour coding
Linked elements are colour-coded in the viewer based on their takeoff status — making it easy to see at a glance which elements are accounted for and which aren't. This visual feedback is one of the key ways Sparkel lets you build confidence in your quantities before they leave the building.