Let's say you have an office standard for how doors and windows should appear in plan view and you want to incorporate this or any other standard as part of your door and window templates. Here are a few things you should know:
1. Save your templates under a new name so users still have access to the door and window templates that ship with Revit.
2. To edit a template change it's file extention from .rft to .rfa.
3. Anything you place in the template can not be deleted once you open the template as a new family file (File... New... Family) so don't try to create new templates this way. Instead you should create new templates by changing an existing template file extention from .rft to .rfa and saving the template under a new name.