Boolean operations reshape overlapping volumes. Use them to merge offices into an open-plan floor, cut a corridor or core out of a block, carve a recessed entrance, or keep only the shared part of two volumes. Snaptrude has five Boolean operations: Union, Difference, Trim, Intersect and Split.

Before you start

Boolean operations work on spaces. In BIM Mode they also work on mass types.
The objects must overlap. The Boolean options appear only when you select two or more overlapping objects.
Selection order matters. The first object you select is the target, which is the object being added to, cut or trimmed.

Run a Boolean operation

Click the object you want as the target.
Add each of the other overlapping objects to the selection, one at a time (for example, Shift + click).
Right-click the selection.
In the Right-click menu, choose the Boolean operation you need: Union, Difference, Trim, Intersect or Split.
Orbit in 3D to check the result.

Note: When you select with a marquee, Ctrl + A (Cmd + A on Mac) or a filter, you don't control which object counts as first, so the result may not be what you expect. For Difference and Trim, click the target first and add the others one by one.

Tip: When objects sit on top of each other, press Tab to cycle through the overlapping objects (Shift + Tab goes back) and pick the one you want.

Choose the right operation

Operation	What it does	Properties kept
Union	Combines the selected objects into one volume.	From the largest object in the selection.
Difference	Subtracts the other objects from the first one you selected.	From the first selected object.
Trim	Cuts the overlap out of the first selected object using the other objects.	The trimming objects keep their own properties.
Intersect	Keeps only the volume where the objects overlap.	Default properties.
Split	Divides the selected objects into separate parts.	Default properties.

"Properties" means the data attached to the object, such as its name or label, Space Type and tags.

Union

Use Union to merge several program spaces, such as a row of offices, into one open-plan space, or to join scattered volumes into a single massing block to read the overall footprint. The result takes its label and other properties from the largest object in the selection.

Difference

Use Difference to create voids, atriums or recessed entrances. Select the volume you want to cut first, then the volumes to remove. The result keeps the first object's properties.

Trim

Use Trim to carve circulation or cores out of a larger volume, for example a corridor or lobby running through a floor plate. Select the space you are cutting from first, then the spaces that do the cutting. The trimming spaces stay in place with their own properties, and the first space loses the overlapping portion.

Intersect

Use Intersect to isolate the shared portion of two overlapping volumes. The resulting object gets default properties, so reassign its name, Space Type and tags afterwards.

Split

Use Split to divide overlapping volumes into separate parts, for example to create sub-zones inside a larger space or to split a landscape zone with a walkway. The resulting parts get default properties.

Note: To slice a mass horizontally by height, by number of divisions or by story, use the Split Volume tool instead.

Tips

Duplicate the objects before a Boolean operation if you want to keep the originals and their data.
Check the result in 3D, where overlaps and voids are easier to see than in plan.
After Intersect or Split, and after Union or Difference where data comes from only one object, review the Properties panel and reassign names, Space Types and tags as needed.
If a result looks wrong, undo with Ctrl + Z (Cmd + Z on Mac), then reselect starting with the correct target.

Troubleshooting

The Boolean options don't appear. Make sure at least two objects are selected and that they actually overlap. Check that the selection contains spaces, or mass types in BIM Mode, rather than other object types.
The wrong object was cut or kept its data. The first object you selected was treated as the target. Undo and reselect, clicking the target first.

Selecting Objects
Split Tools: Split, Split Face and Split Volume
Space Types, Area Types and Opacity
Working with Tags
Keyboard Shortcuts

Boolean Operations