What is hinge backset?
Hinge backset is the dimension from the edge of the hinge to either the stop on the frame or to the edge of the door. For operating clearance, the hinge backset on the door is 1/16″ less than the hinge backset on the frame.
What is the hinge backset on a 1-3/4″ thick door?
For 1-3/4″ thick doors prepped with 4-1/2″ or 5″ butt hinges OR
For 1-3/8″ thick doors prepped with 3-1/2″ or 4″ hinges:
Frame = 5/16″ (edge of hinge to frame stop)
Door = 1/4″ (edge of hinge to edge of door)
For special thickness doors (over 1-3/4″ thick): Hinge size and backset must be specified