# Exporting the Exterior Envelope

Sometimes all you need is the building envelope. You can use the [Merge Rooms](https://docs.pollination.solutions/user-manual/model-editor/commands/alphabetically/me_merge_rooms) command with a high tolerance value to merge the rooms on the floor together quickly. This is also a necessary step for creating [core and perimeter models](https://docs.pollination.solutions/user-manual/model-editor/workflows/creating-core-and-perimeter-models).