Linear dimensions are placed between selected points. The dimensions are aligned to the horizontal or vertical axis of the view. The selected points are endpoints of elements or the intersection of references (for example, the join of 2 walls).
You can use arc end points as references when placing linear dimensions.
Horizontal and vertical dimensions are available in the project environment only. You cannot create them in the Family Editor.
The following illustration shows horizontal and vertical linear dimensions on an irregular-shaped building.