Lets brake down the lock into a few sections and deal with them in a little more detail.
Five lever.
This is the amount of levers that the key has to move in order to allow the bolt to be thrown, when you insert the key into the lock and start to turn the key, levers are pushed up to a height that is in relation to the shape on the key. The more levers the better but for a door lock for a house 5 levers is as much that is available these days, Chubb, many years ago did make a seven lever, check out this blog I did a few months ago about levers on a lock - click here.
Mortice
This denotes that the lock sits in the door. Derived from the mortice and tenon joint that carpenters use to fix two pieces of wood together. Tenon being the projection mortice being the hole. If the lock sat on the door as opposed to in the door, it would be called a Rim Lock
Dead Lock
This is the bolt that projects into the frame to secure the door to the frame. There are two different types of dead lock there is a Dead Lock and there is a Sash Lock both are technically dead locks, save that a sash lock also has a latch as part of the whole lock. from the outside of the door, or for this matter the inside, it is true to say, if you see a door with just a key hole and nothing else around then it is safe to say it is a dead lock, if however, you see a handle on the door, with a key hole in the plate of the handle, then again, it would be safe to say this is a sash lock.
For insurance requirements both are Five Lever Dead Locks and pass as being the minimum security requirement that you should consider on an external door. better, would be to have a British Standard version of the above as then you would have a longer bolt throw, anti drill plates, security curtain inside the lock to reduce the effect of picking the lock as this stops a direct attack against the levers etc.
I very much hope that the above will give you all the information to understand what a five lever dead lock is, what the differences between a dead lock and sash lock are and if you want to go a stage further what you get if you decide on a British Standard Version.
Feel free to email me, direct, pass a comment, or check out our forum for more info and perhaps other peoples comments
Many Thanks for reading
Darrel Walters
CEO

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