DesignBuilder comes with a database of all of the world's time zones including information on daylight savings. This data is sourced from ASHRAE.
If the time zone does not have daylight saving then the text N/A is entered in the Daylight saving from field.
The time zone is selected in model data under Time and Daylight Saving on the Location tab at site level.
Note: you can override daylight savings to be off in the model data by unchecking the Use daylight saving.
Template data can be accessed:
from the Templates tab on the opening screen (if no file is open),
from the Templates tab in the Navigator panel (if a file is open),
by double-clicking on the template icon in the model data,
by clicking on the Edit button when selecting templates from a list.