64mm vs 76mm Tubular Latch: Which Size Do You Need?
64mm vs 76mm Tubular Latch: Which Size Do You Need?
Choosing the right tubular latch is important when fitting new door handles or replacing an existing latch. Two of the most common sizes are 64mm and 76mm tubular latches, but the difference between them can be confusing if you are not familiar with latch measurements.
In this guide, we explain the difference between a 64mm and 76mm tubular latch, what the backset measurement means, how to measure your existing latch and how to choose the right size for your door handles or door knobs.
64mm vs 76mm Tubular Latch: Quick Answer
The main difference between a 64mm and 76mm tubular latch is the overall length of the latch case and the distance from the edge of the door to the centre of the spindle follower.
| Feature | 64mm Tubular Latch | 76mm Tubular Latch |
|---|---|---|
| Overall latch size | 64mm | 76mm |
| Typical backset | Approximately 44mm | Approximately 57mm |
| Common application | Internal doors | Internal and larger doors |
| Suitable for | Door handles and knobs | Door handles and knobs |
Both sizes can be suitable for internal doors. The correct choice depends mainly on your existing door preparation, available space and the position where you want the door handle or knob to sit.
What Is a Tubular Latch?
A tubular latch is a type of door latch installed inside the edge of a door. It works with a pair of door handles or a door knob to allow the door to open and close while keeping it held against the door frame when closed.
The latch contains a spring-loaded follower mechanism. When the door handle or knob is turned, the spindle rotates the follower and retracts the latch bolt, allowing the door to open.
Tubular latches are commonly used with internal door handles, lever handles and door knobs in residential and commercial interiors.
What Does 64mm Mean on a Tubular Latch?
A 64mm tubular latch refers to the overall length of the latch case. It is one of the commonly used sizes for internal doors.
A typical 64mm tubular latch has a backset of approximately 44mm. This means the centre of the spindle follower is positioned approximately 44mm from the face of the door.
The 64mm size can be particularly useful where you want the door handle or knob to sit relatively close to the edge of the door.
What Does 76mm Mean on a Tubular Latch?
A 76mm tubular latch is longer than a 64mm latch and typically has a backset of approximately 57mm.
The additional length provides a greater distance between the edge of the door and the centre of the spindle follower. This can change the position of the handle or knob on the face of the door.
As with a 64mm latch, a 76mm tubular latch can be used with suitable door handles and door knobs, provided the latch is compatible with the door preparation.
64mm vs 76mm: What Is the Main Difference?
The easiest way to understand the difference is to look at the backset.
With a typical 64mm tubular latch, the backset is around 44mm. With a typical 76mm tubular latch, the backset is around 57mm.
This difference affects where the spindle sits in relation to the edge of the door.
For example, if you replace a 64mm latch with a 76mm latch, the centre of the spindle may sit further away from the door edge. This is why it is important to check your existing latch and door preparation before choosing a replacement.
What Is the Backset on a Door Latch?
The backset is the measurement from the front face of the door, where the latch faceplate sits, to the centre of the spindle follower.
It is an important measurement because it determines how far the door handle or knob sits from the edge of the door.
Common tubular latch backsets include:
- Approximately 44mm for a 64mm tubular latch
- Approximately 57mm for a 76mm tubular latch
Always check the manufacturer's stated dimensions because measurements can vary between individual latch designs.
How to Measure Your Existing Tubular Latch
If you are replacing an existing latch, measuring it before ordering a new one can help you choose the correct size.
Step 1: Remove the Door Handle
Carefully remove the existing door handles or knobs from the door. You will normally need to remove the fixing screws and slide the handles away from the spindle.
Step 2: Remove the Latch
Remove the screws holding the latch faceplate to the edge of the door. The latch can then be pulled out of the door.
Step 3: Measure the Latch
Measure the overall length of the latch case. A common latch will measure approximately 64mm or 76mm.
Step 4: Measure the Backset
Measure from the front of the latch faceplate to the centre of the spindle follower. This will tell you the approximate backset of the latch.
Step 5: Check the Faceplate
Before purchasing a replacement, also check the shape and dimensions of the faceplate. Matching the existing preparation can make replacement easier and reduce the need for additional work to the door.
Which Tubular Latch Should You Choose?
There is no single latch size that is suitable for every door. The right choice depends on the existing door preparation and the handle or knob you are installing.
Choose a 64mm Tubular Latch If:
- Your existing latch is approximately 64mm.
- You require an approximately 44mm backset.
- You want the handle or knob positioned closer to the edge of the door.
- The existing door preparation is designed for this size.
Choose a 76mm Tubular Latch If:
- Your existing latch is approximately 76mm.
- You require an approximately 57mm backset.
- Your door preparation is suitable for the longer latch.
- You want the spindle positioned further from the edge of the door.
64mm or 76mm Latch for Door Handles?
Both 64mm and 76mm tubular latches can be used with compatible door handles. The important consideration is the relationship between the latch, spindle and handle position.
Before buying a replacement latch, check the backset and existing door preparation rather than choosing a size based only on the appearance of the latch.
If you are replacing the complete door hardware, it is also worth checking that the latch is compatible with the spindle supplied with your chosen handles.
64mm or 76mm Latch for Door Knobs?
Door knobs can also be fitted with suitable tubular latches. The same principle applies: check the required backset and the existing preparation before choosing the latch.
The position of the knob can affect how comfortable the door is to operate, so selecting the correct latch size is an important part of a successful door hardware installation.
What Happens If You Choose the Wrong Latch Size?
Choosing the wrong latch size can create installation problems.
A replacement latch may not sit correctly in the existing mortice, or the spindle position may be different from the previous latch. This can affect the position of the door handle or knob and may require additional adjustment to the door.
For this reason, it is always worth measuring your existing latch before ordering a replacement.
64mm vs 76mm Tubular Latch Comparison
| Measurement | 64mm Tubular Latch | 76mm Tubular Latch |
|---|---|---|
| Latch length | 64mm | 76mm |
| Typical backset | 44mm | 57mm |
| Typical use | Internal doors | Internal doors |
| Compatible hardware | Suitable door handles and knobs | Suitable door handles and knobs |
| Key measurement | Backset and latch case length | Backset and latch case length |
Frequently Asked Questions
Is a 64mm latch the same as a 2.5 inch latch?
They are commonly used to describe a similar latch size. However, always check the manufacturer's exact metric dimensions rather than relying only on an imperial description.
Is a 76mm latch the same as a 3 inch latch?
A 76mm latch is commonly referred to as a 3-inch latch. As with other latch sizes, check the manufacturer's specifications before purchasing.
What is the backset of a 64mm tubular latch?
A typical 64mm tubular latch has an approximately 44mm backset.
What is the backset of a 76mm tubular latch?
A typical 76mm tubular latch has an approximately 57mm backset.
Can I replace a 64mm latch with a 76mm latch?
It depends on the existing door preparation and the required handle position. Because the backset is different, you should measure the existing latch and check the replacement dimensions before changing sizes.
Do tubular latches work with door knobs?
Yes. Suitable tubular latches can be used with door knobs as well as lever door handles. Always check compatibility between the latch, spindle and chosen hardware.
How do I know which tubular latch I need?
Measure your existing latch, check its overall length and measure the backset from the edge of the door to the centre of the spindle follower. Then compare those measurements with the specifications of the replacement latch.
Shop Tubular Latches at Love Handles UK
Choosing the correct tubular latch is an important part of installing or replacing your door hardware. Whether you need a 64mm tubular latch or a 76mm tubular latch, checking the latch length, backset and existing door preparation can help you find the right option.
Explore the Tubular Latches collection at Love Handles UK to find suitable door latches for your next hardware project.
For more advice on door hardware, explore our guides covering door latches, door handle spindles and door handles.
