Door Backset Distance

Latch bolt projection is the length the latch bolt extends from the door s edge.

Door backset distance.

To do this measure the backset distance of your old lock. The backset is an important measurement as it specifies the distance from the face of the lock to the centre of the keyhole. The most common backset is 2 3 8 but 2 3 4 is also quite common usually used on exterior doors. Latch bolt projection is the length the latch bolt extends from the door s edge.

The measurement is usually 2 3 8 inches for interior doors and 2 3 4 inches for exterior doors. If you dont have any hardware on your door just measure from the edge of the door to the center of the bore hole the large hole where the door knob assembly is mounted. Backset the distance from the edge of the door to the center of the lock bore. Standard backsets are either a 2 3 8 backset or 2 3 4 backset.

Backset distance is the distance from the door s edge to the center of the handle s mounting hole. Other backsets include 2 used by national and lori lock and 5 used by weiser weslock kwikset and others. Select a handle with the correct backset distance the distance from the door s edge to the center of the handle s mounting hole for your door. 2 3 8 inches and 2 3 4 inches.

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. Backset is the distance from the front of the lock to the centre of the spindle as shown here. Also known as passage knobs they do not lock. The outside handle is always locked and has to be unlocked with a key while the inside handle can always open the door.

Pack your locks with a 2 3 8 inch or 2 3 4 inch latch depending on which backset you specify. Two standard backsets are 2 3 8 and 2 3 4. In addition to lasting twice as long as standard door knobs these are made entirely of corrosion resistant materials to stand up to washdown and marine environments. Select a knob with the correct backset distance the distance from the door s edge to the center of the knob s mounting hole for your door.

Latch bolt projection is the length the latch bolt extends from the door s edge. For frequently used doors these handles last twice as long as standard door handles. The most common sizes here are 44mm and 56mm give or take a few millimetres. This allows you to correctly line up with existing holes in the door rather than drilling new ones.

2 3 4 backset distance. Select a handle with the correct backset distance the distance from the door s edge to the center of the handle s mounting hole for your door. Also known as passage handles they do not lock. If you re installing a lockset in an existing door take out the old lockset and measure the backset the distance from the door edge to the center of the lockset hole.