Any borders applied to a layout using Template Styles will be automatically added to final Hi-Res images and layouts during production provided you have selected the following options in the Preferences:

For Composite Layouts:

Preferences -> Hi-Res Production -> Style options -> Composite Prints: Add Borders & Mats

For Traditional Matted Layouts:

Preferences -> Hi-Res Production -> Style options -> Traditional Matted Prints: Add Borders

Note: You can also select to add borders up to the first bevel which is useful for applying a border such as a keyline and space to a print which will be mounted within a traditional mat with a bevel.