Attach across the link
- Reads floors and roofs from the linked structural file
- Sets WALL_TOP_OFFSET automatically per wall
- Handles sloped slabs and rotated links
- Auto-joins touching elements in the host model afterwards
Attach architectural wall tops to floors or roofs living in a linked structural file — WALL_TOP_OFFSET is set automatically, with sloped slabs and rotated links handled.
In Revit, the native Attach Top/Base command can't read a floor or roof living inside a linked structural file — architects have to fake it with hand-built reference planes before attaching each wall one by one. Every time structural adjusts a slab elevation, the whole batch of walls has to be redone.
Because the native Attach Top/Base command can't see a floor or roof living in a linked file, engineers open each wall, build a reference plane at the structural slab's elevation by hand, and only then attach it — repeated across hundreds of walls per floor.
When the underside of a slab or roof follows a slope, WALL_TOP_OFFSET stops being a single number — hand-worked trigonometry drifts by a few centimetres at each point, leaving gaps or walls poking through the slab once you check the 3D view.
Coordination projects often place the structural file rotated off true north from the architectural one; attaching by absolute Z elevation then gets it wrong because the real slab plane sits skewed in the host's coordinate system, forcing a manual coordinate conversion before the offset can even be worked out.
Attaching the wall top doesn't automatically join it to the adjacent columns, beams or slabs — skip that step and stray lines show up in section views, throwing off quantity schedules.
There's no Autodesk App Store add-in that publicly solves "attach an architectural wall top to a floor or roof living in a linked file" — even Autodesk's own community forum flags it as a limitation of the native Attach Top/Base command, which simply doesn't read floors or roofs from a linked model. The usual workaround is copy-monitor or hand-built reference planes per wall. AttachWall reads the linked floor/roof geometry directly, computes WALL_TOP_OFFSET automatically even for sloped slabs or rotated links, then re-joins afterwards — specifically:
The interface is matched to the tool window running in Revit.
Detect MEP passing through walls, floors and beams and create openings with standard clearances.
Split beams and slabs along lines or by two clicks — a solid-boolean algorithm with true multi-line support.
Merge collinear beams and slabs into a single element, with un-merge to reverse it.