How do Door Latches Work?

Door latches are an essential part of any internal door. Without a latch, your door will swing gently (or even wildly!) with every draught of air that moves through your house. As well as making your home cold, this would sound incredibly annoying – and you’d soon get bored of getting up every five minutes to push the door closed again.

This is why every interior door needs a latch. Yet not everyone appreciates why or knows what to look for when picking one out, and this can make an otherwise simple decision unreasonably difficult.

We’ve put together this introduction to door latches to help you find the right latch for your internal door. We’ll explore what door latches are and how the different parts work together to help keep your internal doors functioning at their best. We’ll look at different latch types too, and even the differences between a door latch and a door lock.

What are door latches?

At its most basic, a door latch is a mechanism that protrudes from a door to hold it closed. With internal doors, a latch is usually used on its own, but with exterior doors, it is often coupled with a locking mechanism.

Latches are used across a whole range of doors, from cupboard doors to cars and even appliances like ovens. This wide range of uses means there is a wide range of different latches available. But, when it comes to external and interior doors, latches tend to be made of metal, as this gives the strength to hold the weight of the door against the frame. There are still a variety of shapes and designs though.

What are the parts of a door latch?

Door latches are technically made up of two parts: the latch and the strike. These parts function together along with other door furniture to operate.

Latch Bolt

This is the part of the latch that extends from the door. It is a significant latch component as it is the part that holds the door in place.

Faceplate

This is a metal plate that sits on the edge of the door to protect it, as well as the latch mechanism. It is also where you fit the screws that anchor the latch in place.

Interior/Exterior knob or lever

This is the main visible part of the door handle, which is used to operate the latch by twisting or pressing down. Along with the rose or base plate, this is technically part of the handle which is attached to the latch assembly, rather than part of the latch itself.

Latch Assembly

This is the case that houses the main latch mechanism that the latch bolt retracts into when the door is opened.

Rose

The rose is also part of the handle, rather than the latch. It is the plate that sits on the door to anchor the handle to the door’s surface  The ‘rose’ name comes from the round shape – if this plate is longer and extends a long way above or below the doorknob or lever, it is called a backplate instead.

Spindle

The different sides of the door handle are joined together by a long thin piece of metal called a spindle. When you turn the door knob (or press down on the handle) the spindle rotates and activates the latch mechanism to retract the bolt. This releases the door and lets you open it.

What is a strike plate?

Latch bolts extend from the door and fit into a hole (or keep) in the door frame. This hole is usually surrounded by a metal plate – this is the strike plate. Strike plates provide strength to the door frame and protect both the frame and the latch bolt. This is particularly important with exterior doors where the strengthened frame increases security – however, even internal door latches can cause damage to a wooden frame or door jamb if they aren’t fitted with a plate. 

Another benefit of strike plates is that their robust surface guides the latch bolt into the keep in the door frame. Finally, a strike plate will create a much neater finish than you get with the raw cuts visible.

What is the difference between a door latch and a door lock?

The essential difference between door locks and door latches is that a door lock mechanism offers a higher level of security. A door lock needs the correct key to operate it – you can’t move it from the locked position without one. In most cases, that key can be removed, though when it comes to thumb-turn locks and other similar locks, the key for the locking mechanism is fixed permanently in place inside the lock body.

This type of door lock is most commonly used in internal doors where privacy is required rather than security. Most often bathrooms are fitted with simple thumb turn or privacy locks. When it comes to external doors like your front door or patio doors, multi-point mortice locks must be used to create a suitable level of security.

What are the different types of door latches?

The most common latches used for internal doors are:

• tubular latches
• spring latches (spring bolt latches)
• rim latches

There are actually a whole host of further latch types available, including swing, gravity, and hook and eye latches but they don’t tend to be used on doors very often. Spring latches are a lot more common. For more information about the different types of door latches, please take a look at our guide to different types of door latches.

Ready to learn more?

Check out these articles to learn more about installing doors.

• How to Choose the Best Front Door Lock
• Everything You Need to Know About Door Hardware
• Choosing Handles for Internal Doors
• How to Replace a Shootbolt (With Pictures)