Union C-Series 3G114 5 Lever Non-British Standard Mortice Deadlock for use on timber doors hinged on either the left or right. The deadbolt can be locked or unlocked by the key from either side.

The keys are suitable for doors up to 50mm thick.

The 3G114 locks are force resistant, anti-drill, anti-pick, and have anti-saw security features. These deadlocks are non-handed and are designed for wooden doors. This mortice lock has a square forend and square end strikeplate.

Chubb Deadlock For Prison Grill Door

The Union 3G114 mortice dead lock is a Union C Series mortice lock, which has been fitted to homes and businesses for decades. Originally made by Chubb, you may find these feature the distinctive Chubb mortice lock brand when replacing an old lock. This product is identical and just features the new Union branding. These mortice locks do not meet the requirements of British Standard BS3621:2007. Please refer to the 3G114E for locks that comply with British Standards. In line with a number of other mortice locks, these locks feature a silver lock case but they have unique measurements that identify them from other mortice locks. While the case width features standard 67mm (2.5″) and 79mm (3″) sizes, the backset measures just 40mm on the 67mm width case and 53mm on the 79mm width case. Please refer to the line drawing for details. Please note that Union have discontinued the original, non British Standard, sash lock version of this lock, the 3K74, but the E3K74 (BS3621 version) is still available. The deadbolt throws 14mm and features hardened pins to protect against sawing attack. The deadbolt can be locked and unlocked from either side by use of the key. This lock is supplied with 2 key hole escutcheons, in a matching finish to the lock for both the internal and external sides of the door. It also comes with a striking box in a grey finish. Suitable for use on doors up to 54mm thick. The thickness of the door is determined by the length of the keys. If you require this lock to be fitted to a very thick door, we may be able to supply extra long keys. 

These locks are not handed and can be used on doors hinged on the left or right, which open inwards or outwards. 

Supplied with 2 brass keys as standard. We can cut additional keys for this lock, just select whether you’d prefer genuine or copy key blanks and the quantity required from the associated products on this page.

Should you require more than one lock to work on the same set of keys, these locks can be keyed alike by our inhouse locksmith team. We can typically dispatch the same day (larger quantities may require longer).

We stock a range of associated parts to these locks, including key blanks, rebate sets for use on double doors and levers. Please select the products you require from the associated products on this page.

These locks are not suitable for use on a fire door. Please refer to the details on 3G114E version of this lock if you wish to use these locks on a fire door.

Union have manufactured high-quality, British designed locks and door hardware for more than 180 years. While their brand has evolved and grown to include a larger family of products over time, they all share a common purpose: a commitment to first class quality and design, with products that make the lives of their customers easier. 

From humble beginnings in 1840, Union has grown from a family business to become a leader in British designed locks and door hardware around the world. They started in Willenhall, the heart of the British lock-making industry in the 19th Century. Today, Willenhall is home to their state-of-the art manufacturing facility and headquarters – an area steeped in heritage and history for the locks and door hardware industry.

Mortice lever locks (sometimes called mortise locks) are commonly fitted to wooden doors but can also be found used in steel, aluminium, and composite doors. They are locked from both the inside and outside with the key which throws the deadbolt. By definition, a mortice lock is fitted (“morticed”) within the door, rather than being fitted to the face or surface of it.

There are multiple types of lever lock in use in the UK. Dead locks (mortice dead locks) are operated by a key only whereas sash locks (mortice sash locks) feature a dead bolt and a latch which is operated by a handle (often a lever handle). Both lever locks with throw the dead bolt into a strike plate. The strike plate on sash locks also accepts the sprung loaded reversible latch.

Lever mortice deadlocks can be used for fitting to front or back doors and to internal doors and external doors, but we’d always recommend fitting a British Standard BS3621 product to external doors for maximum security. You should also check with the houseowner’s insurer’s requirements on both residential properties and commercial properties. You may find lever locks fitted to commercial properties but cylinder lock cases operated by a cylinder or pin tumbler lock are more common mortice locks fitted in commercial environments.

Lever mortice door locks are commonly used for internal doors too. These tend to be 3 lever mortice locks where the requirements for security and burglary prevention are lower.

When replacing an existing lever mortice lock, you may find that your replacement mortice lock is larger than the one that you are replacing. This may be because you are improving security, such as upgrading to a lock with thicker, anti-drill hard steel plates or because the forend length, forend width or the design of the lock has changed. The hole for the lock can normally be made larger with a hammer and chisel. This can also be the case for strikes, which may have changed design.