Mortise style lock sets vs the common cylindrical lock sets

Mortise style locks are the most secure form of an entry set. A special cut in the door allows a longer and thicker mortise to slide into the pocket in the door itself, providing superior protection. These types of locks require special door preparation. This kind of lock was commonly seen in homes prior to 1940 (before the introduction of bored cylindrical locks), but is still available today in single cylinder, double cylinder, and dummy set . In Europe they are widely use in all domestic properties and more recently they have been becoming more commmon in comercial and upmarket residential in north america.

Still the tubular style or cylindrical locks are more common in north america where they can be found on all types of doors, mostly in interior residential and office doors. They are quite easy to install, they not require expensive tools and much knowledge to install them.

Mortise locksets 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. This mortise must be created with precision and requires a special tool and expertise to get it done right without damaging the door.

Mortise locksets are usually very durable and can often last the lifetime of a house. 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. The locking mechanism is very substantial and all parts are precision milled, making the mortise lock superior in strength to a typical bored cylindrical lock.

The body of the lock houses the parts that actually work the lock, including workings for the knob or handle, latch, and deadbolt. When you look at the frame of a door with a mortise lock, you will see a solid metal plate that is flush with the frame and securely screwed in place. Within that plate is an opening, and the locking device on the door, usually a thick, steel bolt, slides into that opening (or mortise) when it is turned with a key. The result is a very secure doorway.

Like any lock, there are pros and cons to mortise locks. The biggest drawback to a mortise lock is the skill needed to install it. Because the frame of the door must be carved out to accommodate the lock body, familiarity with woodworking and the tools of the trade are a must in order to achieve a solid fit.



 From a historical perspective, with the development of bored cylindrical locking devices, the mortise lock began to fall out of favor. The primary reason was the skill required to install it. For quite some time these locks were mostly found on older buildings, doors and furniture which were constructed prior to the advent of newly developed locks. However, since the lock itself is so strong, its security potential couldn't be denied, and the use of the mortise lock is slowly returning in popularity in commercial structures and high end residential buildings.