You can edit a building location's settings even if there are elements already inserted on it. The elements will update to reflect your changes.
To edit a building location:
Select Settings
> Building Locations, or click the Building Locations button
on the on the Basic View Control toolbar.
In the Building Locations dialog, click on the property you want to change. You can change location names or any of the numerical settings.
Type the value you want.
Press Enter.