View Full Version : Term for a door knob/lock dimension?

Stephen Tashiro
03-27-2010, 8:43 PM
What terminology describes the distance between a door knob and the nearest edge of the door?

I need to replace an exterior door knob mechanism. Its knob is so near the weatherstripping on the door jamb that I tend to scrape my hand when I open the door. I'd like to move the hole for the door knob several more inches away from the jamb. But in looking for a new mechanism, I don't know what specification in a door knob/lock describes this dimension.

Walter Plummer
03-27-2010, 9:42 PM
Hi Stephen. It is called the backset. Most residential knobs are 2 3/8" backset and most commercial knobs are 2 3/4" backset. I have seen knobs with larger backsets but I don`t know how hard they are to find. I think I would try asking a locksmith first.

Clarence Miller
03-27-2010, 10:22 PM
Hi Stephen,

Most knobs (keyed entry) have an adjustable backset for the latch being 2.375 and 2.75. I make doors for a living and happen to operate the machine that cuts the hardware for the doors in my division. Odd backsets are very unusual to run into and are usually for flush pulls on sliding doors or doors with a roller latch installed.
This being said I would recommend that you install a lever action instead of a round knob with a 2.75 backset. When we measure the backset on one of our doors we measure from the center of the lock edge. So if the the door is beveled, drill from the hinge side (this is the wide side of the door where the barrel of the hinge is exposed, usually the inside of the door) and add 3/64" to take into account the bevel. When I have to drill a cylinder lock I use the plastic jig that I picked up at a hardware store.
Hope this helps.

David Prince
03-27-2010, 10:22 PM
Do they still make those old style door knobs that are in the middle of the door? That would keep you from hitting your knuckles!:D


Clarence Miller
03-27-2010, 10:30 PM

I found a 5" backset at the following site

Part No. 16-126

The price isn't bad either, especially for non-standard hardware.

Stephen Tashiro
03-28-2010, 12:13 AM
Thanks to all for the information. Now I must meditate on the idea of using a lever action vs using the bolt in that interesting Schlage link.

Rich Engelhardt
03-28-2010, 8:14 AM
Now I must meditate on the idea of using a lever action vs using the bolt in that interesting Schlage link.
We went lever about 4 years ago & I'd never go back to a knob.
It's just too handy.
I usually have something in one hand and a ring of keys in the other.
It's mindless simple operate the lever as opposed to trying to "two finger" a knob.

Kudo's to my wife for suggesting it. I'd have never, in a million years, imagined how handy it would be until we had one.

Myk Rian
03-28-2010, 8:23 AM
We also have levers. Really nice.
You may not have to change the backset if you go with them.

Mike Cutler
03-28-2010, 8:29 AM

We also switched to the lever action door sets. It's really convenient when carry things in and out of the house.

Neal Clayton
03-28-2010, 3:12 PM
if you need an odd size, older locks tended to be different than newer ones (specifically, 2.25, 2, or 2.5), therefore historic restoration type places have those sizes. i order mine from rejuvenation and house of antique hardware.

Horton Brasses
03-29-2010, 1:41 PM
Ball and Ball (www.ballandball-us.com) and Whitechapel (www.whitechapel-ltd.com) should both have nice historic ones and different backset options. Both will be quite expensive but excellent quality.

Levers vs. knobs: We debated this quite a bit and went with knobs. If you have young kids around the lever is too easy to open. If it weren't for that though I think the levers are very nice and would prefer them.

I want to keep the kids in the room their supposed to be in as needed (works for a while anyway). :o