In the U.S. there are two common backsets for residential door locks, 2-3/8" and 2-3/4". The backset is the distance from the edge of the door to the center of the 2-1/8" bore hole. We will pack your locks with a 2-3/8" or 2-3/4" latch depending on which backset you specify.
The backset is the distance from the edge of the door to the spindle mechanism on the latch. Usually a 63mm case measurement will have a 44mm backset and a 76mm case measurement will have a 65mm backset. The backset you choose is where your door knobs will sit on the door (where the spindle goes through).
Choosing Latches for your Door Handles or Knobs
The most common size has a casing that is 64mm in depth and the distance to the middle of the square operating spindle is 44mm. This size of the latch is used for most lever handles on back plates, where the width of the backplate is about 40-45mm.
We generally recommend that a 76mm Overall Latch Size is ordinarily the best size for most lever handles. However the shorter 64mm Overall Size should be used where the door is glazed, to minimize the risk of hitting the glass rebate when drilling to fit the latch.
Backset is measured from the centre of the keyhole to the edge of the lock. Most backsets are commonly measured at either 44mm (for a 64mm (2½”) lock) and 56mm (for a 76mm (3”) lock). Typically a lock adjacent to a glass panel will be 2½” (44mm) and otherwise 3” (56mm), but you should always measure to be sure.
In the U.S. there are two common backsets for residential door locks, 2-3/8" and 2-3/4". The backset is the distance from the edge of the door to the center of the 2-1/8" bore hole.
In the United States, there are two common backsets for residential door locks: 2-3/8 inches. 2-3/4 inches.
Most door latches on the market today are adjustable, so that you can change the backset between 2-3/8" and 2-3/4". This brief article will explain how to adjust the backset on a door latch. This method is applicable to all Designers Impressions door knobs and levers, as well as most Callan door knobs and levers.
Determining the backset and overall length can be done by removing the existing latch and taking the dimensions. If the door handle or knob is still in place and you'd rather not remove it then you can measure from the edge of the door to the centre of the spindle hole (centre of the handle/knob).
Measure the distance from the face of the gate to the back edge of the rose (round bit of the ring handle); this gives you the measurement that needs cutting from the spindle so the ring handle fits onto the gate.
There are many different sizes, but as we've already mentioned, the most common are 64mm and 76mm (2.5" & 3" when using imperial measurements).
Door handles, pulls, latches, locks and other operating devices shall be installed 34 inches (864 mm) minimum and 48 inches (1219 mm) maximum above the finished floor.
The next measurement to consider therefore is the backset. Backset sizes refer to where your handle will sit on the door - this is the part of the lock where your door handle or door knob will be connected to the tubular lock. For a 63mm case length measurement, the backset is usually approx 45mm.
To determine the correct backset measurement for your door, you need to measure the distance from the edge of the door to the center of your cross bore. The two standard backset measurements in North America are 2 3/8 inches and 2 3/4 inches.
What is meant by 'Backset'? 'Backset' is the distance from the front of the lock to the centre of the spindle as shown here. If you intend to use new locks or latches on an old door, replacing your old ones, you will need to make sure the new one fits into the hole in the door.
Case depth is also a common main concern when it comes to sash lock size, with the two most common being 64mm (2.5 inches) and 76mm (3 inches) for 3 and 5 lever sash locks.
Flat latches are similar to tubular latches in that they are both embedded into the structure of a door and function similarly. Flath latches differ in that they are a solid box type mechanism with a spring action more durable than a tubular latch.
If your door handle is not springing back correctly it is likely to be one of a few issues: The fixings have been overtightened causing the lever bearing to bind against the door face, or causing the door to compress the latch mechanism inside the mortice and stop it from operating correctly.
When a door latch won't catch, it's because the latch doesn't align with the hole in the strike plate. Sometimes you can clearly see the misalignment. If not, do the “lipstick test.” Smear lipstick on the latch and stick masking tape to the strike plate.
Backset Information
When looking for any deadbolt, knob, or lever product, it is important to measure the backset of the door on which it is going to be installed. This will ensure the lock you are purchasing will fit properly. The backset is measured from the center of the hole for the lock to the edge of the door.
What is the backset on a Night Latch? The backset on a night latch is the distance from the centre of the keyhole to the edge of your door, you will find most night latches will have a 60mm backset.