If you must it is always better to round down than round up.
Measurements for door locks.
All standard bored locks ansi 115 2 161 61l type for mortise lock ansi 115 1 86 type all locations must be altered 3 8 lower and standard strike asa type.
This helps to ensure that your door will fit.
The standard bore is 2 1 8.
That s the side without the lock if it s not an entry door and you re not sure.
Many older doors had bores that were been smaller.
Shop door knobs handlesets.
Use the smallest figure as your measurement.
The distance between the edge of the door and the center of the lock hole.
Measure the diameter of the holes currently cut out of your door so you can select a new door lock that fits those dimensions.
Measure from the inside edge of the trim on one side to the inside edge of the trim on the other side to get your jamb width if there s trim installed or simply measure the jamb if it s unadorned.
1 measure from the center of the door knob hole to the edge of the doorway to find the size of the door set.
Measure the width of the door in 3 locations.
Before purchasing a lock measure your door s backset cross bore and thickness to ensure you find the right fit.
Usually the backset measures 2 3 8 inches or 2 3 4 inches.
These sizes are the overall length of the latch or the case.
If one wants to replace their locks on doors that have smaller diameter holes there are 2 options.
Dummy sets have no latch and are surface mounted so you can install a dummy set wherever you choose on the door.
Measure the height of the door right in the middle.
You ll want to measure sliding doors from outside of your home looking at the exterior of the door.
Your cylinder locks should be as flush as possible with the handles maximum projection is 5mm if you current lock sticks out by more than 5mm either side of the hanldes then choose a smaller size.
Most of the current locks require the standard 2 1 8 bore.
Opening heights 3 0 through 4 11 15 16 centered in door height not frame.
Although they can come in different sizes the two most common sizes in the uk for internal door latches are 63mm and 76mm.
As for how to measure a door frame.
Stand inside the open door facing the jamb.
Pack your locks with a 2 3 8 inch or 2 3 4 inch latch depending on which backset you specify.
Cylinder door locks are not difficult to replace if you have basic diy skills you only need two measurements.
2 3 8 inches and 2 3 4 inches.
Measure from the floor to the underside of the trim at the top of the door.
Before you learn how to change door locks measure the space where you ll install the replacement.
When measured to the spindle mechanism the backset then they translate as 44mm for the 65mm case and 57mm for the 76mm case.
Take care to measure carefully as matching the size can be especially problematic in older homes.
