Baldwin Mortise Locks - How to measure your door for a mortise lock

Baldwin Mortise Locks Door Measuring Guide

How to measure for a mortise lock:

Measure stile of door (measurement from edge of door to edge of paneling or glass, see A on diagram at right)
Determine hand of door (see chart below)
Measure door thickness

If door is pre-drilled, also measure:

Backset of existing hole(s), measure from the edge of the door to the center of the hole, usually either 2 3/8" or 2 3/4" (see B on diagream at right)
Measure from center of top hole to center of bottom hole (only if two holes are drilled)
Measure from floor to center of bottom hole

Not all mortise lock trim styles will cover existing pre-drilled door applications.
Please contact us with any questions.

A. Stile B. Backset

The Measurement of the Stile (letter A on diagram) determines the best backset lock for your application. Ideally the lock trim should sit in the center of the door stile. Choose the backset that is closest to half the distance of the stile. For example, with a 5" stile a 2.5" backset would be the most appropriate.
*Don't forget to consider the overlap distance of the jam when the door is closed.

Please do not hesitate to contact us with any questions about determining the best backset for your door.

HOW TO DETERMINE HAND OF DOOR
baldwin mortise lock

HAND OF DOOR IS ALWAYS DETERMINED FROM THE OUTSIDE
Here are a few rules to follow:

The outside of an exterior door is the street or entrance side.
The outside of a room door is the hall side.
The outside of a single communicating door is the side from which the hinges are not visible when the door is closed.
The outside of a closet door is the room or hall.

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