Door Lock Buying Guide

Looking for the best lock for external timber doors? 5-lever deadlocks are ideal because they’re very difficult to break into – if they’re British Standard BS3621 approved, they’ve been rigorously tested against all the common methods used by burglars.

With the British Standard approval, they could bring down the cost of insuring your property because they offer a high level of protection – they’re also recommended by the police.

5-lever deadlocks are more expensive than their 3-lever counterparts to reflect the higher security offered by these models.

If you’re looking to secure internal wooden doors or add privacy for bedrooms or bathrooms, 3-lever deadlocks are a common choice because they’re less expensive yet still difficult to force open.

They’re also aesthetically pleasing – just the keyhole and faceplate of the locking mechanism are seen when the door is closed. 3-lever deadlocks can also be keyed alike, meaning you’ll need just one key for multiple locks – making them safer in emergency situations.

3-lever mortice deadlocks don’t meet the BS361 British Standard for external doors, so are only suitable for internal doors.

3 and 5-lever sash locks – used for timber doors – are a reliable and versatile lock with a bolt that slides into the door frame and a latch to operate it. This means you don’t need to worry about it locking behind you if you forget your key on busy mornings!

Like deadlocks, because they’re fitted inside the door, they’re very difficult to force open. As well as this, most of the lock being stored inside means you have lots of choice to customise what you can see, such as the door handle, to fit your style.

It’s important to remember that, like deadlocks, only 5-lever sash locks can be British Standard BS3621 approved, so you should ensure they’ve passed these checks before relying on them to secure your property.

Euro sash cases – like classic sash locks – are often used for external doors, and have a deadbolt that slides into the door frame and a spring-loaded latch. They're operated with a replaceable cylinder to make changing the locks easy and inexpensive.

A thumbturn cylinder allows the door to be unlocked from the inside by turning the thumbturn on the cylinder, making it ideal for emergency situations. However, it requires a key when used from the outside.

It’s important to check that the euro cylinder is 3 star kitemarked to ensure it’s anti-pick, anti-drill, anti-bump and anti-snap. We always recommend to use a 3 star rated cylinder as it provides the best protection for your door.

Euro dead cases, like mortice deadlocks, secure a door with a bolt that slides into the door frame – but with a replaceable cylinder locking mechanism that makes it inexpensive and easy to change the locks.

Dead cases are versatile and customisable; you can choose from a wide range of escutcheons – protective and decorative keyhole covers – to find the right style for your doors.

Unlike sash cases, if the door is locked, you need to unlock it with a key – meaning you’ll want to keep a spare close by for emergency situations.

Night latches are often used on front doors alongside a mortice lock. A metal bolt slides into a case attached to the door frame. They are unlocked from the outside using a key, and a thumb turn from the inside of the home.

They automatically lock the door behind you so you don’t need to remember to lock it if you’re leaving in a rush – but you can put night latches ‘on the latch’ to avoid this when needed.

Standard night latches shouldn’t be relied on to secure a property on their own unless they’re British Standard approved. Pair night latches with a BS3621 5-lever mortice lock to meet insurance regulations and police recommendations.

Rim locks are the oldest type of lock used in the UK and Ireland. They’re easily attached to the surface of a door and feature a sliding bolt which slides into a case on the door frame. They’re used alongside mortice locks on front doors, or to keep garden sheds secure.

Because they’re mounted on the surface of the door, there’s less damage to the door or door frame compared to mortice locks – which cut large holes into the woodwork. This also means the locks can have stylish decorations to suit your taste.

Rim locks aren’t secure enough for external doors because they’re only attached to the surface meaning they’re easier to overcome; you’ll need to use them with a BS3621 approved lock if you want to use them for anything other than internal doors.

Push button locks offer high security for internal and external doors, and are operated using a keypad with a code set by the user – you won’t need to give keys to everyone who needs access. When the correct code is entered, a bolt slides out of the door frame to unlock the door.

The code can be changed at any time – making it easy to control who’s allowed in and out without having to change the entire lock.

It’s important to consider who the code is being shared with – it’s much easier to lose track of than a key! And in the case of battery-operated locks – the battery could run out.