Mortice Locks

Mortice Locks: Types, Sizing, and Security Standards

Discover the different types of mortice locks, including deadbolts, latches, and sash locks, suitable for sliding, timber, composite, steel, and aluminium doors. Learn about sizing options, key operation, security standards like BS 3621, BS 8621, and BS 10621, and essential features for optimal protection.

Mortice Locks Overview

Mortice locks, also known as mortise locks, are commonly used as various types of door security. They come in different variants, such as deadbolts, latches, or a combination of both, known as sash locks. Sliding doors often utilize hook and claw bolts. These locks are installed inside a lock pocket or mortice cut out of the door, making them a popular choice. If you have doors in your home, there’s a good chance that at least half of them are fitted with mortice locks. They are available in two sizes, depending on the width of the door stile, and can be operated using either a cylinder key or levered key.

Sizing and Measurement

Determining the correct size for your mortice lock is crucial. Measure the distance from the door edge to the centre of the keyhole to identify the size you need. If the distance measures 44mm, you will require a 67mm mortice lock. On the other hand, if the distance measures 57mm, you’ll need an 80mm mortice lock. Remember that mortice locks should not be installed on doors that are less than 44mm thick. However, if your door is slightly off the recommended thickness, a reinforcing kit can be used. This kit bolsters the door’s strength by bolting through it and sandwiching the door and lock together. The lock’s bolt is thrown into a boxed keep, which is cut into the doorframe. Cheaper locks may have a simple flat plate with a hole for the bolt.

Security Standards and Insurance Requirements

Many home insurers require at least one of the locks on your external doors to either have five levers or be certified to meet BS 3621 standards. It’s essential to verify that your mortice lock meets these requirements. Multipoint locks are not considered in this case; instead, we are referring to timber doors, some composite doors, some steel doors, and certain old aluminium doors that use mortice deadlocks or sash locks. To determine if your mortice lock is certified to BS 3621, look for the British Standard kitemark on the lock’s faceplate. If the kitemark is absent, it could be a lock from Europe certified to the EN 12209 standard. Check the lock’s faceplate or key for the manufacturer’s details and consult your insurer to confirm its acceptability. If further information is required, it may be necessary to consult a locksmith for an expert opinion. Please ensure someone remains at home if you choose to remove the lock for assessment. If your current lock does not meet your insurer’s standards, it is advisable to replace it with an acceptable lock. For any discussions or agreements with your insurer regarding lock suitability, request written confirmation to ensure clarity.

Pricing and Types

Mortice locks are available at different price points. The least expensive levered mortice deadlock without British Standard certification typically starts around £15. In contrast, a BS 3621-certified levered mortice deadlock lock can start at £45, with cylinder mortice deadlocks certified to BS 3621:2007+A1:2009 priced up to £90. It is important to note that the latest version of BS 3621 is BS 3621:2007+A1:2009. However, insurers may still accept locks certified to the previous version, BS 3621:2004, or earlier iterations. Confirm with your insurer for specific requirements. Mortice sash locks are similarly priced to mortice deadlocks.

Mortice Deadlocks – BS 3621 Thief Resistant

Mortice deadlocks certified to BS 3621 are typically installed on entrance doors to homes, complementing rim night latches. For optimal locking distribution between the mortice lock and rim night latch, it is recommended to fit these locks approximately one-third up from the bottom of the door. If the locks are not in this position, seek advice from a police Crime Prevention Officer or a Master Locksmith. A BS 3621:2007+A1:2009-certified mortice deadlock incorporates various security features, including a minimum of 2,000 key differs for lever-operated locks. This high number of key differs means a potential thief would need to carry 2,000 keys specific to your lock to have a chance of unlocking it, making it highly secure. For cylinder-operated locks, the cylinder must be BS EN 1303-certified with Grade 5 key security, a minimum Grade 0 attack resistance, and a Grade 2 drill attack resistance. Additional features include hardened steel spindles in the brass deadbolt or a hardened steel deadbolt, a hardened steel plate over the lock casing to prevent drilling, and a sturdy boxed keep to receive the deadbolt.

Mortice Deadlocks – BS 8621 Thief Resistant – Keyless Exit

If you share the main entrance door with another household, it is advisable to install a BS 8621:2007+A1:2009-certified mortice deadlock. These locks offer keyless egress from the inside, preventing accidental lock-ins.

Mortice Deadlocks – BS 10621 Thief Resistant – Dual Mode Lock Assembly

If you reside in a flat with an alternative means of escape other than the private flat entrance door, consider fitting a BS 10621:2007+A1:2009-certified mortice deadlock. These locks provide dual-mode functionality and possess the same security attributes as BS 8621-certified locks. They allow you to lock the internal thumb turn from the outside, knowing that anyone accidentally locked inside can safely exit using the alternative means of escape.

Mortice Sash locks

Mortice sash locks closely resemble mortice deadlocks but also include a live bolt or latch alongside the deadbolt. They are typically positioned just below the centre of the door, avoiding the joint between the mid rail and latching stile. Private flat entrance doors often feature mortice sash locks, supported by a pair of mortice security bolts on back and side doors of houses. The same security standards and features mentioned for mortice deadlocks apply to mortice sash locks.