Difference Between T-Handle, Deadbolt, and Slide Garage Door Locks

Your garage is one of the most important access points to your home. For many households in the UK, it is used daily for cars, bicycles, tools, or even as a secondary entrance into the property. Securing it properly is essential, and the choice of lock plays a central role.

With so many types of garage door locks available, it can be difficult to know which is best for your needs. Among the most common options are T-handle locks, deadbolt locks, and slide locks. Each works in a slightly different way, offers its own advantages and disadvantages, and is suited to particular styles of doors and usage patterns.

This guide explores the difference between T-handle, deadbolt, and slide garage door locks, helping you understand how each one works and which might be the right choice for your property.

Why garage door locks matter

A garage door is usually the largest single door on a property. Without a secure lock, it can become the weak point intruders look for first. Older or poorly maintained locks are often targeted because they are easier to force. Choosing the right lock is not only about convenience but also about deterring crime and protecting your belongings.

In addition, insurers expect homeowners to take reasonable steps to secure their property. Having the right type of garage lock, properly fitted, may reduce the risk of invalidating cover if a burglary occurs.

An overview of the three lock types

Before comparing them in detail, here is a simple outline:

• T-handle locks are the traditional external locks found on many up-and-over doors. They are operated with a key from outside and usually connect to locking rods inside the door.
• Deadbolt locks are robust internal bolts that slide into the door frame. They are often used as supplementary security on up-and-over or sectional doors.
• Slide locks are internal manual bolts, common on roller doors, that prevent the curtain from being lifted.

Each serves the same overall purpose but does so in a different way.

T-handle garage door locks

How they work

A T-handle lock takes its name from the handle on the outside of the garage door, which is shaped like the letter “T.” The handle is connected through the door panel to a locking mechanism inside. Turning the key releases or secures rods that extend horizontally into the door frame.

When locked, the rods hold the door firmly against the frame, preventing it from being pushed open.

Advantages of T-handle locks

• Widely available and familiar to most homeowners.
• Straightforward to operate with a key.
• Affordable to replace if damaged or worn.
• Compatible with many up-and-over doors commonly used in the UK.

Disadvantages of T-handle locks

• Basic models are not particularly resistant to forced entry.
• Keys are often simple and can be copied easily.
• The external handle itself can be targeted by thieves using brute force.
• Exposed to the weather, meaning corrosion can be an issue if not maintained.

Best suited for

Traditional up-and-over garage doors where convenience and cost are priorities. For greater security, T-handle locks can be combined with internal deadbolts or upgraded to high quality versions with stronger barrels.

Deadbolt garage door locks

How they work

A deadbolt lock uses a solid metal bolt that slides directly into the door frame. The bolt can be operated from inside the garage, either with a key or a thumb turn. Some designs are linked to external cylinders, allowing you to lock and unlock from outside as well.

Because the bolt extends directly into the frame, deadbolts provide a strong physical barrier. They are often used as secondary locks to reinforce existing systems.

Advantages of deadbolt locks

• Very strong and resistant to brute force.
• Provides a clear additional layer of protection.
• Simple design with fewer moving parts, meaning reliability over time.
• Can be fitted to many types of garage doors, including up-and-over, sectional, and side-hinged.

Disadvantages of deadbolt locks

• Often need to be locked and unlocked from inside, which can be inconvenient for daily use.
• Installation may require drilling into the frame.
• Without an external cylinder, you cannot open the garage from outside if the deadbolt is engaged.
• More expensive than a simple T-handle replacement.

Best suited for

Garages used mainly for storage rather than daily vehicle access, or where homeowners want to add an extra level of security. They are also useful for detached garages in rural or less visible locations, where intruders have more time to attempt entry.

Slide garage door locks

How they work

Slide locks, also known as shoot bolts, are manual bolts fitted to the inside of the garage door. They consist of a metal bar that slides into a hole in the side track or directly into the wall or floor. They are commonly used on roller doors, where the bolt stops the curtain from being lifted.

Some slide locks include holes for padlocks, adding another level of security.

Advantages of slide locks

• Simple design that is easy to use.
• Affordable and widely available.
• Very effective at preventing roller doors from being forced upwards.
• Can be fitted as an additional lock to most types of doors.

Disadvantages of slide locks

• Usually only accessible from inside the garage, which is inconvenient if the garage is your main entry point.
• If the door is motorised, using slide locks without disengaging the motor first can damage the system.
• Security depends on the strength of the installation and whether a padlock is used.

Best suited for

Roller garage doors or as supplementary security on sectional doors. They are ideal for garages that are not used daily, or for homeowners who want an internal lock to reinforce external mechanisms.

Comparing the three types

Ease of use

T-handle locks win for everyday convenience, as they can be operated from outside with a simple key. Deadbolts and slide locks often require you to be inside the garage, which is less practical if you use the garage frequently.

Security

Deadbolts are generally the strongest of the three, providing solid resistance against brute force attacks. Slide locks are also strong when fitted properly, particularly with a padlock. T-handle locks offer basic security but are more vulnerable unless upgraded.

Cost

T-handle locks are the cheapest to buy and replace. Slide locks are also very affordable, though they may need to be used alongside another lock. Deadbolts are more expensive but provide the highest level of protection.

Installation

Replacing a T-handle lock is usually straightforward, requiring only basic tools. Fitting a deadbolt or slide lock may require more drilling and alignment work. Professional installation is sometimes recommended for deadbolts to ensure maximum strength.

Best scenarios

• For daily access garages, a high quality T-handle with supplementary bolts is often best.
• For garages mainly used for storage, a deadbolt provides reliable strength.
• For roller doors, slide locks are the most effective choice.

Combining locks for maximum security

In many cases, the best solution is not to choose one type of lock but to combine them. For example, a T-handle lock provides daily access convenience, while internal deadbolts or slide bolts add reinforcement when the garage is not in use.

Layered security is particularly important if your garage connects directly to your home. The more barriers you provide, the less appealing your property is to opportunist intruders.

Maintenance tips for all lock types

Regardless of the type of lock you choose, regular maintenance is essential.

• Lubricate moving parts every six months with graphite powder or silicone spray.
• Check for rust or corrosion, especially on external handles.
• Tighten any loose fixings to prevent rattling or wobbling.
• Replace worn keys before they damage the barrel.
• Keep the area around internal locks clean to prevent dirt from interfering with movement.

Security upgrades worth considering

Alongside locks, UK homeowners can boost garage security with other measures:

• Garage defender bars placed outside the door prevent it from being lifted.
• Smart sensors send alerts if the door is opened unexpectedly.
• Motion-activated lighting deters intruders at night.
• CCTV cameras provide visible deterrence and evidence if needed.

Locks are vital, but they work best as part of a layered approach to security.

A practical UK example

A homeowner in Birmingham with an older up-and-over garage door relied for years on a basic T-handle lock. After a nearby burglary, they decided to upgrade. They fitted a new high security T-handle with anti-drill features, then added two internal deadbolts that could be engaged when the garage was not in use. The result was both daily convenience and stronger overall security.

In another example, a family in Manchester installed a roller garage door. They soon realised that while the motor included an automatic lock, adding slide bolts gave them extra reassurance when they were away on holiday. They padlocked the slide bolts for maximum protection, ensuring the door could not be forced upward.

These examples show that different types of locks have different strengths, and often the best choice is a combination tailored to your needs.

Final thoughts

The difference between T-handle, deadbolt, and slide garage door locks lies in how they work, their level of convenience, and the security they provide. T-handle locks are common and practical but less secure on their own. Deadbolts are robust and provide excellent reinforcement, though they are less convenient for daily use. Slide locks are simple, affordable, and particularly effective on roller doors.

For UK homeowners, the right choice depends on how you use your garage, what type of door you have, and how much security you require. In many cases, combining locks is the most effective way to balance convenience and safety. By understanding the strengths and weaknesses of each type, you can choose with confidence and ensure your garage is as secure as the rest of your home.