Many main entrance doors to a block of flats, for example, have a basic Yale nightlatch or similar fitted. While this is convenient for the tenants it fails to meet two criteria…
Meeting insurance approved security levels
Allowing for easy fire escape in emergencies
A standard Yale type nightlatch arrangement is easy to use but also vulnerable to being picked/slipped or bypassed by people who should not be entering (non-keyholders). If you want to improve the security of the lock a BS3621 nightlatch can be fitted. It features an armoured cylinder escutcheon and automatically deadlocking latchbolt when the door is closed. However these nightlatches also have the ability to have the inner handle deadlocked with the key, stopping it from being operated if someone smashes the glass.
This is fine for a domestic property but totally unsuitable for a communal entrance door.
The reason is that in the event of an emergency the residents need to escape quickly. It can potentially be fatal if someone has locked the inner handle, as without the key it cannot be unlocked and therefore allow the lock/door to be opened and escape made. You cannot have the residents being forced to go back into their smoke filled flat, for example, to find a key in their panic.
So Yale make a version specifically to cater for this requirement. Depending on the size of the lock it is called the PBS3 or PBS4. The British Standards these locks adhere to is BS8621 (as opposed to BS3621 for the lockable version). Here is a picture of a PBS4 fitted by Linacre locksmiths.
The inner handle has no keyway so cannot be deadlocked – fire escape regulations will always override security. The safe evacuation of residents is always the first concern.
So if you are concerned what is fitted to your own communal doorway, or if a landlord looking to check you have the right lock in place, give Linacre Locksmiths a call and we can give the correct advice. http://www.linacrelocksmiths.com
A very useful system is masterkeying and keying alike lock cylinders, where multiple locks are required to be operated with the minimum of keys. On a simple level a homeowner may want their front and back door locks to be keyed alike to save having two different keys. This means that both locks are keyed alike, and share the same key, so one key can operate either door. Many upvc french doors (double doors) have a keyed alike cylinder in each door. Linacre Locksmiths often get asked to do this for homeowners who need locks changed due to lost or stolen keys for example.
However this advantage of keying alike locks is also useful to landlords who may have 3 or 4 bedrooms let out to students for example. Each student wants to lock their own door of course and also have a key to the entrance doors. Which means normally one key for front door, one key for back door and one key for their room. Three keys. Why not just have one! Here is an example of a simple masterkeying and keying alike lock suite.
The house has four bedroom doors, with front and back entrance doors. These entrance doors have been keyed alike (the same). As can be seen, the landlord has 3 master keys which can operate every lock in the house. But the students have their own keys which can do only their own bedroom but also either entrance door.
A similar suite is in the following picture. However in this instance the landlord also wanted 3 keys that just operate the entrance doors only. This is so they can give a tradesperson one of these keys (for instance a gas boiler service engineer) so they can enter the property to do the work but not be able to access any bedrooms. Again the entrance doors are keyed alike, and again the tenant has a key that does their own room and entrance doors but no other. The landlord has master keys which can operate every door.
These are simple examples of course but are ideal for landlords with a house of multiple occupancy. There are many higher levels of masterkeying and keying alike such as those found in hotels for example. Locks can be grouped into sub-groups each with their own master keys, and with a set of grand master keys to open them all.
Linacre Locksmiths can provide this service and the benefits to homeowners and landlords is obvious.