What Coil Size Do I Need for Roller Shutter Slat?

Roller Shutter Slat Coil Size Guide (Before Forming)

Roller shutter slats are interlocking metal profiles used in doors for shops, warehouses, garages, and industrial facilities. These slats roll into a compact coil when opened and provide security, durability, and weather protection when closed.

The most important starting point in production is selecting the correct coil size before forming — especially the coil width, which determines the slat coverage, interlocking performance, and rolling behavior.

For roller shutter slats, coil size directly affects:

• Slat coverage width
• Interlocking performance
• Rolling diameter and flexibility
• Structural strength
• Production efficiency

This guide explains exactly what coil size you need before forming roller shutter slats.

What Is Included in “Coil Size”?

Coil size includes:

• Coil width (most critical)
• Thickness (gauge)
• Coil weight
• Coil inside diameter (ID)
• Coil outside diameter (OD)
• Material type and coating

All must match both slat design and forming equipment.

1. Coil Width (Primary Factor)

The most important factor is the coil width before forming, based on the developed strip width.

For roller shutter slats, this includes:

• Slat face (visible width)
• Hook/interlock sections (top and bottom)
• Curvature radius (for rolling action)
• Reinforcement ribs (if included)
• Bend allowances

Coil width calculation:

👉 Coil width = slat face + interlock hooks + curvature + bend allowances

Typical coil width ranges:

• 60 mm – 100 mm → small shutters / kiosks
• 100 mm – 150 mm → standard commercial shutters
• 150 mm – 250 mm+ → heavy-duty industrial shutters

👉 Coil width must include full interlocking geometry

2. Thickness (Gauge)

Roller shutter slats use light to medium gauge materials to allow rolling.

Typical ranges:

• 0.6 mm – 0.8 mm → light-duty / residential
• 0.8 mm – 1.2 mm → standard commercial
• 1.2 mm – 1.5 mm+ → heavy-duty / high-security

Thickness affects:

• Rolling ability
• Strength and security
• Slat weight
• Coil diameter when rolled

3. Coil Weight

Coil weight depends on production scale.

Typical coil weights:

• 1 – 3 tons → small production
• 3 – 6 tons → standard production
• 6 tons+ → high-volume lines

4. Coil Inside Diameter (ID)

The coil ID must match the uncoiler.

Common sizes:

• 300 mm – 400 mm → small coils
• 508 mm (20”) → standard
• 610 mm (24”) → larger systems

5. Coil Outside Diameter (OD)

OD depends on coil thickness and weight.

Typical OD:

• 800 mm – 1500 mm+

Must match:

• Uncoiler capacity
• Handling systems
• Production layout

6. Material Type and Coating

Material selection is critical for durability and appearance.

Common materials:

• Pre-painted galvanized steel (PPGI)
• Galvanized steel (GI)
• Aluminum (for lightweight shutters)

Material affects:

• Corrosion resistance
• Surface finish
• Weight
• Rolling performance

Why Coil Size Is Critical for Roller Shutter Slats

Roller shutter slats must interlock perfectly and roll smoothly.

If coil size is incorrect:

• Slats may not interlock properly
• Rolling performance may be poor
• Door may jam or misalign
• Coverage width may be incorrect
• Structural strength may be reduced

Accuracy is critical for function and durability.

Roller Shutter Slat Geometry (Key Feature)

Roller shutter slats typically include:

• A curved face section
• Top and bottom interlocking hooks
• Reinforcement ribs (optional)
• Smooth rolling geometry

These require:

• Precise coil width
• Controlled forming radius
• Consistent interlock dimensions

Incorrect coil size affects:

• Interlocking performance
• Rolling diameter
• Door operation
• Visual finish

Common Coil Size Mistakes

• Incorrect width
  Slats do not interlock correctly
• Ignoring interlock sections
  Weak or unusable connections
• Wrong thickness
  Poor rolling OR weak security
• Incorrect material choice
  Reduced durability or performance
• Poor slitting quality
  Edge defects affecting hooks

Machine Matching (Critical)

Before ordering coil, confirm your machine supports:

• Coil width range
• Thickness range
• Maximum coil weight
• Ability to form interlocking slats
• Material compatibility

👉 Coil size must match machine + slat design

What Buyers Must Confirm Before Ordering Coil

Always confirm:

• Slat profile design and dimensions
• Interlocking system type
• Required strength/security level
• Developed strip width
• Material type and coating
• Coil weight
• Coil ID / OD
• Machine limitations

Never estimate — always ensure compatibility with shutter system.

Final Thoughts

For roller shutter slats, the coil size before forming defines interlocking performance, rolling behavior, and strength.

Getting the coil size right ensures:

• Smooth rolling operation
• Strong and secure slats
• Accurate coverage width
• Efficient production
• Long-term durability

Roller shutter slats must perform under repeated use — coil size accuracy is essential.

FAQ

What coil size do I need for roller shutter slats?
You need the correct coil width, thickness, weight, ID/OD, and material based on slat design and application.

What is the most important factor?
Coil width — it defines interlocking and coverage.

Why is thickness important?
It affects both rolling ability and security strength.

Can all slats use the same coil size?
No — sizes vary depending on shutter type and application.

Can coil size be adjusted during production?
No — it must be correct before forming.