In document preferences, the Associate dimensions field is selected by default, allowing dimensions to be associated with objects, including walls and wall components. The dimension must be applied between two vertex points for the dimension to be associated.
Appearing on the drawing as a parametric constraint, the association of a dimension can be deleted through the Edit Constraints dialog box (Modify > Edit Constraints); if the dimension is resized, the association is lost. This is also true if the dimension is relocated, but not the object to which it is associated.
Associative dimensions can exist across layers of the same scale. To apply an associative dimension across layers, Layer Options must be set to Show/Snap/Modify Others and both layers must be in a Top/Plan standard view. Associative dimensions can be created on viewports in annotation edit mode (see Creating Annotations for Sheet Layer Viewports).
If associative dimensioning is not used, dimensions cannot be associated with objects after they are placed (except for chain dimensions).
Changing the length of a linear associative dimension in the Object Info palette breaks the association of a dimension. When using associative dimensions across layers, changing the scale of a layer breaks the association.