Why are deadbolts never put on both sides of the door?

[darklide]

Why are deadbolts never put on both sides of the door?

Example:

A deadbolt put where the hinges are?

[Solomon]

If you put a deadbolt at the same side as the hinges the door wouldn't even open, and even if my some kind of magic it did, it'd offer very little security... if you pushed or pulled on the side of the door opposite the hinges it'd be very easy to lever the lock out of place, even a 10 year old could do it. Try it... get someone to push as hard as they can against the inside of a door on the same side as the hinges, then push it open from the other side using the handle. It'll take virtually no effort on your part nomatter how hard they push... you don't remember this from physics class?

[lockedin]

There are doors with multiple locking points. Usually the actual locking mechanism is limited to one, and usually it's not on the opposite side, but on the top or the bottom.

[Raymond]

As long as the hinges are on the inside of the door or the hinge is made so the pin cannot be removed, there is little value in putting a lock on that side. Many locksmiths recommend replacing the short screws and installing LONG screws on the hinges. The screws must at least go through the 3/4 inch trim of the standard door frame and into the 2 x 4 inch studs supporting the frame.

This makes the middle of the door the next weak link in the chain. Use reason, common sense and do what you can afford.

[Evan]

Wow... It's clear not many people have seen the sort of locks that residents install on apartment doors in NYC... 4-point door locks are quite common there... The 4 locking bolts are all operated simultaneously from a knob in the center of the door on the inside or by a rim cylinder mounted in a protection plate on the outside of the door...

~~ Evan

[Engineer]

Here in the UK anyway, you can buy "Hinge bolts". These might not be quite the same as you mean, but they are quite similar in action.

They are permanently fixed inside the door and the bolt, slides into the hole as you close the door. They make it much more difficult for someone to kick the door in, or to get in if they attack the hinges.

http://www.google.co.uk/images?hl=en&q= ... 49&bih=806

[Raymond]

Evan is exactly correct about the multi-point locks used in some locations. These actually reinforce the whole door. The point is that some locations demand a higher level of security due to the crime rate and type of crime. I see too many houses secured by nothing but a Kwikset knob and landlords that only buy $4.00 imports and expect great security. I see too many new houses where the contractor only cuts out the strike hole by 1/2 inch for a 1 inch deadbolt and the people are so unaware that they do not notice for years until I am rekeying and explain to them.

[raimundo]

@darklide if you look at some safe doors you will see that even they often do not have an active bolt on the hinge side, however there are lugs on the door and strike holes in the frame that lock this side of the door. and closeing the door puts those lugs into the holes,
Try this, screw a thick bolt into that edge of the door, then put some of the gf's lipstick on the end of the bolt and close the door as far as you can, this will put a lipstick mark on the place where you need to drill the strike hole, when you have the bolt go in about half an inch when its closed, your hole is ready for a strike plate to strengthen the wood grain, this may have to be mortised, so screw it on over the hold, then use a utility knife to cut a line about as deep as your mortise needs to be around the strike plate. then get your sharpest wood chisel and start inside this line driving the chisel at a low angle to lift a chip that is already cut at the end by that utility knife line.
You will have to make the metal strike plate yourself, a common one will not work well.
You can also strengthen the wood frame if its not some kind of pasteboard and is real wood, put some long sheetrock screws into the wood about six inches above and below the lock installation just to tie the wood grain together.

and as Raymond has said make sure the strike hole is deep enough for the bolt to go in all the way, if the bolt is not allowed to go to the full depth, you do not have a 'dead' bolt, you have a live bolt. I a medeco is installed in this way in common wood door frame, it can be opened in seconds with an ice pick, I won't say how, thats restricted.