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Mortise & Cylindrical Locksets

door locksetLocksets are used by each of us virtually everyday. They are one of those items that we constantly take for granted. Locksets provide us with convenience, privacy and security. However, many people do not realize that there is a wide range in features, quality, durability and function with respect to locksets. I believe this is due in part to the fact that we are exposed to locksets as children. They are those shiny knobs that are on every door. What could possibly be so difficult about locksets? Plenty!

Two Basic Types

Locksets are available in two different basic configurations: mortise and cylindrical. Once installed, it is difficult, from a distance, to distinguish between the two. However, they are vastly different in function and installation.

Mortise locksets are those that require a mortise in the edge of the door for installation purposes. The guts of the lockset are contained within a thin box or case which fits into the mortise. The mortise which needs to be created is often quite deep. It is not uncommon to create a cavity, 7/8 inch wide, six inches long and four inches deep. Believe me, that is a big hole in the edge of a door! This mortise must be created with precision. It requires a special tool to do it expertly with minimal chance of damaging the door.

Mortise locksets are usually very durable and can often last the lifetime of a house. Residential uses of these locksets are usually reserved for front doors, where you often wish to install a fancy lockset.

These locksets also offer a unique feature. Virtually every mortise lockset has a built-in heavy duty deadbolt. What's more, this deadbolt can be activated in conjunction with unlocking the standard door latch. You simply have to insert your key into one slot and turn the key a little more than one full turn.

Mortise locksets are often very expensive. They usually are solid brass with highly decorative finishes. The locking mechanism is very substantial and all parts are precision milled. They are not really overpriced when you compare them to other locksets.

So what are the holes for?

Those predrilled holes you commonly see in doors are created for cylindrical locksets. These are the locksets that most of us are familiar with. These locksets derive their name from the shape of the lockset mechanism.

Cylindrical locksets come in a variety of styles. There is also a wide range of quality and durability with these locksets. You can purchase some cylindrical locksets for as little as $8 to $10. That should tell you something!

These locksets have one tremendous advantage over mortise locksets. They can be easily and quickly installed by a rookie who has a little bit of patience and hand-eye coordination. The installation does not require expensive tools, especially if you order the door predrilled for both the lockset and the latch.

Because virtually every cylindrical lockset requires the same sized hole for the lockset and the latch, predrilling is the only way to go! There is generally only one measurement you need to specify. This is called the 'backset'. Backset is defined as the distance from the edge of the door to the center of the lockset hole. The two sizes most commonly used in residential work are 2 3/8 inch and 2 3/4 inch. Most residential locksets use the 2 3/8 inch backset.

Which one is right for me?

In my building career, I installed 50 to 100 cylindrical locksets for every mortise lockset. My own home contains 20 to 30 cylindrical locksets of varying quality and style. However, I did install a beautiful and durable mortise lockset in my front door.

Many people like the appearance of the thumb latch handle which is common on many mortise locksets. This same look is available on certain cylindrical locksets.

However, remember that cylindrical locksets almost always require a separate deadbolt lock for security purposes. This lock requires that you insert your key into an additional slot to unlock the deadbolt. Also, the deadbolt requires additional predrilled holes. My advice is to shop around and see which lockset will best serve your needs. Good luck on your next project!

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