I’ve got a Yale nightlatch lock (model Yale 84 nightlatch) on front door but it’s not a deadlocking one so if someone breaks the glass in the door they can just reach in and open it.

If I buy the same size deadlocking Yale one,(Yale 85 deadlock nightlatch) is the deadlock part in the barrel or the main latch part? Just want to know if I can swap the latch bit but keep my original cylinder so don’t need to go and get lots of new keys cut.

Thanks

According to the Yale website, both the 85 deadlatch and the 84 nightlatch are supplied with the same Yale model 1109 cylinder, which suggests you should be able to use your existing cylinder and keys.

I would be careful to get one with the same backset and finish, which should allow you to use the existing staple.

However IANAL.

Ignore

Can anyone who breaks the window not flick up the snib to remove the deadlock?

If you want to stop people smashing your window to open the door you need the P1 /L2 locking deadlatch

The deadlocking mechanism is in the night latch part of the lock and not the cylinder meaning you’d not have to cut a whole bunch of new keys.

HOWEVER,

As wwpaddler says, you’d need a Yale P1/L2 to stop people reaching in to unlock the night latch through a broken window.
An ERA British Standard Double Locking Nightlatch would also do the same job as would a Yale PBS1.

All three of those options require a key to be easily at hand incase of fire and you need to beat a hasty exit.

I have been a locksmith for over 15 years.

thanks for the replies.

This is one i’m looking at:
https://www.yale.co.uk/en/yale/couk/products/mechanical/nightlatches/8589—deadlocking-nightlatch/

features:
Features:

Inside handle can be deadlocked by a reverse turn of the key in the outside cylinder after closing the door
Snib to deadlock or hold back the latch
deadlocked by the snib button internally, making the lock inoperable by key or handle
Anti-bump
Supplied with 1109 cylinder
2 keys supplied

^^ says internal handle can be locked from outside? Or is this a mistake. I was assuming it means can lock handle, and this means snib wont work, but when you go turn key back in the house it cancels the handle deadlock

Dont really want the internal handle key locking type as i’ve always thought them a bit of a hazard if you forget to unlock the handle and theres a fire.

We have this one, but I think the design is dangerous…

There are two independent lock barrels, so if you deadlock it from the inside (to stop the hand through glass scenario) you can’t then get out without a key and opening it from the outside (to come in) doesn’t unlock the inside handle. Fire escape risk IMO.

^^ says internal handle can be locked from outside? Or is this a mistake. I was assuming it means can lock handle, and this means snib wont work, but when you go turn key back in the house it cancels the handle deadlock

From the outside, on locking, you’d turn the key 360deg in the opposite direction which would deadlock it (stop the handle from being used).
On opening from the outside the key would need to be turned ~420deg to open it and cancelling the deadlocking action.

We have this one, but I think the design is dangerous…

There are two independent lock barrels, so if you deadlock it from the inside (to stop the hand through glass scenario) you can’t then get out without a key and opening it from the outside (to come in) doesn’t unlock the inside handle. Fire escape risk IMO.

You don’t have to use the dealocking function all the time. Arguably you want the higher security when your home is unattended, and obviously it is not an increased fire risk then. When you are at home, you can choose not to deadlock it or you could deadlock it but leave the key in the lock on the inside.

Incidentally it would be a good idea to check your household contents insurance policy document and see what requirements it makes about locks. It might only require that all locks are put into effective operation when the house is left unattended, but it might also specify that the door locks are to a minimum standard, e.g. BS3621, which models 84 and 85 do not meet.