The ContinueDimension command continues a linear, angular, or ordinate Dimension from an extension line of the previous or specified Dimension.
To create continuous Dimensions:
When the last dimensioning command created a linear, angular, or ordinate Dimension, you are prompted to select a point as the second extension line origin. In other cases, you are prompted to select an existing linear, angular, or ordinate Dimension as the base Dimension.
The same request appears if you press Enter at the prompt to specify a second extension line origin.
When creating linear continuous dimension chains, the Dimension text displays the distance between the extension line you append to and the point you select.
Access
Command: ContinueDimension
Menu: Dimension > Continue
Ribbon: Annotate > Dimensions > Continue
Toolbar: Continued