The Collada (DAE) format is a standard file format for exchange of Mesh data. The Arch Module can import meshes from .dae files, and export Arch and other Shape-based objects to the .dae format.
Note that imported objects will be Mesh objects, and will need to be turned into Shapes or Arch objects for optimal use. The Arch Module has several tools to help you in performing that operation.
The Collada import functionality in the Arch module depends on pycollada. If it is not installed on your system, Collada import/export will be disabled.