Door Locks 101: What is a Keyway Anyway?

Keyway” is the term for the shape of the interface between a lock and its key

It’s most clearly seen when you imagine the cross section of the “blade ” of a key.  If you look at a key like you’re going to jab yourself in the eye with it, you will notice that the grooves and ridges that run down the sides back toward the handle are not always the same in size, shape, or number from key to key.  This is regardless of the shape of the key‘s teeth – those bumps and ridges that resemble a mountain range if viewed from the side.

The keyway is what prevents you from even beginning to push the wrong key into the wrong slot.  If you have the right keyway but the wrong key, you can easily slide the key into the lock ¬≠but it won’t turn.  See the difference?  Wrong keyway: square peg, round hole.  Right keyway, wrong key: right hotel, wrong room.  (I know I’m showing my age here, but trust me, hotels used real keys in olden times).

What does this have to do with the price of rice in China?  Well, most of the buildings we build or remodel have either one of two keyways that are proprietary to the lock manufacturer, so you can’t replace just the guts (cylinder) of the lock and leave the rest.  We run into this problem all the time when we are trying to match a new lock in a house to its existing key(s).  If a house has a Schlage/Baldwin keyway, we can’t buy a lock with a Kwikset/Yale keyway and expect to have it re-keyed to the original house key.  Or vice versa.

Just to be clear, there at least 1000 different keyways in use at this moment in history.  And those are just the mass-produced examples.

Of course, there are examples of lock manufacturers making replaceable tumblers.  Any competitor’s tumbler that’s keyway compliant can be swapped in, but these are fairly rare.  For example, Kwikset once made a tumbler that was Schlage compliant, but quit production after 2 years.  This cross-pollination came from the Kwikset “Titan” line of locks and handsets. The Titan is Kwikset’s top of the line.  Many Locksmiths will tell you that the Titan line is on par with any good quality residential lock/handset system.  I have my doubts.  I know that the Titan line of keyed locks has an innovative feature that lets the locks be re-keyed with unprecedented ease.  Maybe this is why locksmiths have a soft spot for the Titan.

Some 3rd party manufacturers make tumblers that convert from one keyway to another, but they’re not very good quality.  And not always available.

So, if you can choose, should you use the Schlage/Baldwin keyway or the Kwikset keyway?

Answer:  Always try to stick with the Schlage/Baldwin keyway, but if you have to match a Kwikset keyway we recommend Yale products over Kwikset.  I’m sure there are others as well.  Yale has the most keyways available within one line of locks, as far as we know.  And their hardware is just fine, as a rule.

Neither H&H nor I have any vested interest in any lock manufacturer, particular keyway or ANY industry group that does.  I just know what my 20+ years working closely with door hardware tells me.  This is a crappy place to skimp when it comes time to finish out a building project.

Maxim:  When choosing finishes for a building project, as a function of day-to-day use, the more you have to touch a building part, the more time and money should be spent.

Good door hardware FEELS good.  Heavy, precise door handles/hardware tell the occupant that they are not only safe, but that they are home.

– Sam (Connect with me at +SamHagermanHH)

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