How To Measure Your Mortice Sashlock
When it comes to replacing your lock, you want to ensure that you get it right first time; therefore measuring your existing lock correctly is vitally important. This guide shows the methods required to measure your mortice sashlock.
The illustration above shows the different parts of your lock that you need to measure.
They are as follows:
A- Case Depth (Measurement taken from the forend to the end of the lock case
B - Backset (Measurement taken from forend to centre of keyhole and centre of latch spindle)
C - Case Height (The height of the lock case)
D - Centres (Measurement taken between centre of keyhole and handles)
E - Forend Length - (Section of lock that is visible when fitted into a door)
F - Forend Width
The most important measurements to get correct are the backset and case depth, these determine the distance from the edge of the door that the keyhole and handles will be.
Standard case depth sizes are 64mm and 76mm.
Standard backset sizes are 44mm and 57mm.
If you are ever unsure of a particular measurement, you can always bring your existing sashlock into the shop for us to measure, or send us a picture of your existing lock at:
