55mm vs 77mm Roller Garage Door Slats: What’s the Difference?

When choosing a new roller garage door, one of the specifications you are likely to come across is the size of the slats. The two standard options are 55mm and 77mm roller garage door slats, but what does the difference in size actually mean for your garage?

Both can provide a neat, space-saving alternative to a traditional up-and-over garage door, but they are generally suited to different opening sizes, requirements and budgets.

In this guide, we compare 55mm vs 77mm roller garage door slats and explain what you should consider when deciding which option is right for your home.

What Are Insulated Roller Garage Door Slats?

A roller garage door curtain is made from a series of horizontal twin-walled aluminium slats with a polyurethane foam core that connect together. When the door opens, these slats travel vertically up the guides before rolling around the barrel inside the box at the top of the door.

The slat measurement refers to the approximate height of each individual profile. Therefore, a 55mm slat is smaller and more compact than a 77mm slat.

Although a difference of 22mm might not initially sound significant, the larger 77mm profile is also a thicker slat providing additional strength over the smaller 55mm slat, and ideal for larger garage doors.  

What Are the Benefits of 55mm Roller Garage Doors?

The main advantage of a 55mm roller garage door is its compact design.

Because the individual slats are smaller and slightly thinner, they fit into a tighter and more compact roll size of 205mm x 205mm.   This is particularly useful where the amount of head room above the lintel is limited or if you want to fit the box under the lintel but still want to maximise the height.

EasyFit Garage Doors’ 55mm roller doors use a smaller guide channels than its larger 77mm alternatives, helping to maximise the drive through width when doors are fitted within the opening.  

A 55mm door can therefore be a good choice for:

• Smaller garage openings
• Garages with restricted headroom to maximise height
• Helps to maximise the opening width when fitted within the opening
• Providing heat and sound insulation
• Homeowners looking for a more cost-effective electric roller garage door

For many standard domestic garages, a 55mm roller door can provide all the convenience required without moving up to the larger 77mm lath door.

What Are the Benefits of 77mm Roller Garage Doors?

A 77mm roller garage door uses larger and thicker slats, creating a more substantial overall curtain.

The increased profile makes 77mm lath doors particularly well suited to larger garage openings, for both width and height where additional strength and rigidity are required.

EasyFit’s 77mm roller garage doors also use larger guide channels, creating a more substantial installation around the opening.

Depending on the particular product selected, choosing a 77mm roller door can also give you access to additional security features such as Secured by Design that are not available on 55mm lath roller doors.

A 77mm roller garage door is suitable for :

• A wider garage opening
• A taller garage opening
• A larger or double garage
• Greater emphasis on strength and security
• Enough headroom for the larger roller box
• Heat and sound insulation

Which Slat Size Is Better for Larger Garage Doors?

As a garage opening becomes wider, the roller door curtain needs to retain its strength and security.  For this reason, 77mm slats are the better choice for larger openings up to 5500mm wide. 

There are maximum width and height specifications for every roller garage door regardless of slat size. Always check that the particular size of lath door you are considering is suitable for your garage measurements, the position and exposure when choosing rather than assuming either slat size can accommodate any opening.

Do 77mm Roller Garage Doors Need More Headroom?

Yes.

Larger 77mm slats create a larger roll size of 300mm x 300mm so more head room is required if the roll is being fitted above the opening.  

By comparison, a 55mm lath door uses a compact roll of 205mm x 205mm, making it particularly useful where headroom is restricted.

This difference can be important if your garage has a low ceiling, lintel, pipes, shelving or other obstacles close to the top of the opening.

Before ordering your garage door, accurately measuring the opening width, opening height, side room and headroom will help determine which installation options are possible.

Are 77mm Slats More Secure Than 55mm Slats?

Slat size is only one part of roller garage door security.

The larger 77mm profile provides a stronger curtain for larger openings, but overall security depends on the complete door system, including the guides, locking system, controls and installation.

For example, EasyFit Garage Doors offers a variety of different 77mm doors with varying levels of specification. The Secureroll Classic 77mm is available with enhanced security features and has achieved Secured by Design accreditation.

Anti-lift locking systems are available on both 55mm and 77mm doors, preventing the curtain slats from being forcibly opened from below.

If security is an important factor in your decision, compare individual roller door specifications rather than judging security purely by whether the curtain uses 55mm or 77mm slats.

Which Is More Expensive: 55mm or 77mm Roller Garage Doors?

A 55mm roller garage door will generally be the more economical of the two options.

Its smaller slats, guides and overall construction can make it a practical choice where you want the convenience of an electric roller garage door without requiring the specification of a larger 77mm system.

A 77mm door will normally cost more because of its larger.

However, price should not be the only consideration. Choosing a door that is appropriately sized for your opening and provides the specification you require is more important than simply selecting the cheapest slat size.

Should I Choose 55mm or 77mm Slats?

The right answer depends largely on your garage and what your priorities are for the door.

A 55mm roller garage door could be the better option if you have a smaller opening, limited headroom or simply want a compact and economical roller door for everyday domestic use.

A 77mm roller garage door is likely to be more suitable if you have a wider and taller opening, want a more substantial construction or are looking for higher-specification security options.

You should also consider how the door will be fitted. Roller garage doors can be installed in different positions depending on the available space around your opening, so your measurements may influence which door and slat size works best.

Compare 55mm and 77mm Roller Garage Doors at EasyFit

There is no single slat size that is best for every garage. The right choice depends on your opening size, available headroom, installation position and the level of security and performance you require.

EasyFit Garage Doors offers roller garage doors using both 55mm and 77mm insulated aluminium slats, giving homeowners options for different garage sizes and requirements.

By measuring your opening and comparing the available specifications, you can choose a roller garage door that provides the right balance between compact dimensions, strength, security and price for your property.