What Coil Width Do I Need for an IBR Roof Sheet? Full Guide

What Coil Width Do I Need for an IBR Roof Sheet? (Full Coil Size Guide)

Short Answer

A standard IBR (Inverted Box Rib) roof sheet with a finished cover width of 686 mm typically requires a coil width between 760 mm and 820 mm.

The exact coil width depends on rib height, trapezoidal profile geometry, material thickness, and roll forming tooling design. IBR panels require more coil width than corrugated sheets due to deeper ribs and sharper bends.

Why Coil Width Matters in IBR Roll Forming

Coil width is critical for achieving accurate profile formation and maintaining production efficiency.

If the coil width is incorrect, problems will occur during both manufacturing and installation.

If the coil is too narrow:

• The profile will not fully form
• Ribs will be incomplete or distorted
• Panel width will be incorrect
• Side laps will not align properly

If the coil is too wide:

• Excess material waste
• Increased production cost
• Feeding and tracking issues
• Reduced efficiency

Coil width directly affects:

• Roll tooling performance
• Entry guide alignment
• Material tracking through the machine
• Final panel consistency

Correct coil width ensures accurate forming, reduced waste, and reliable installation performance.

Profile Dimensions & Coil Width Overview

IBR Panel Dimensions (Left Side Concept)

Cover width: 686 mm
Overall width: approximately 720–750 mm
Rib height: 32–38 mm
Pitch: typically 171–200 mm
Overlap: standard side lap

Coil Width & Development (Right Side Concept)

Typical coil width: 760–820 mm
Flat development width: approximately 760–820 mm
Includes: ribs, bends, and overlap sections
Allowance factors: material thickness and tooling
Variation: depends on profile design

Understanding Coil Width vs Cover Width

A common mistake is assuming the coil width equals the finished cover width.

This is incorrect.

Cover width is the usable width after installation.

Coil width is the flat strip before forming.

The coil width must include:

• Rib formation
• Bend allowances
• Overlap sections
• Material deformation during forming

This is why a 686 mm IBR panel requires approximately 760–820 mm coil width.

Estimated Development (Flat Blank Width)

The coil width is based on the developed flat width of the profile.

This includes:

• Rib geometry
• Bends and angles
• Side lap
• Material stretch

Basic concept:

Flat width = cover width + rib development + overlap + bend allowance

Example for IBR:

Cover width: 686 mm
Rib development: approximately 50–80 mm
Overlap: approximately 20–40 mm
Bend allowance: approximately 10–20 mm

This results in a coil width of approximately 760–820 mm.

Why IBR Requires More Coil Width

IBR profiles are designed for strength and structural performance.

They require more material because:

• Deeper ribs
• Trapezoidal geometry
• Sharper bends
• Defined structural shape

This makes IBR:

• Stronger than corrugated profiles
• Suitable for larger spans
• Widely used in commercial and industrial construction

Typical Coil Width Range

Standard IBR (686 mm cover width): 760–820 mm

Light gauge IBR: 740–780 mm

Heavy gauge IBR: 800–860 mm

Exact values depend on profile design and tooling setup.

Common Material Thicknesses

Typical thickness range:

0.30 mm – light-duty roofing
0.40 mm – standard roofing
0.47 mm – common commercial use
0.50 mm – heavy-duty applications
0.60 mm – industrial applications

Thicker materials:

• Require more forming force
• Increase bend allowance
• May slightly increase coil width

Materials Used for IBR Roof Sheets

Common materials include:

PPGI (pre-painted galvanized steel)
Galvanized steel (GI)
Galvalume (Aluzinc)
Aluminum

Material differences affect:

• Flexibility
• Springback
• Forming performance

These factors can slightly influence coil width and final profile accuracy.

Industries Using IBR Roof Sheets

IBR is one of the most widely used roofing profiles globally.

Common industries include:

Commercial buildings
Industrial warehouses
Factories and production facilities
Retail developments
Residential roofing (in some regions)

IBR is popular because it offers:

• High structural strength
• Good water drainage
• Clean modern appearance
• Reliable performance

Key Factors That Affect Coil Width

Profile geometry
Deeper ribs increase material usage

Material thickness
Thicker material increases bend allowance

Overlap design
Side lap adds to total width

Tooling design
Different machines produce slight variations

Machine setup
Entry guides and forming system affect feeding width

Common Mistakes When Selecting Coil Width

Using corrugated or Trimdeck coil width for IBR
IBR requires more material due to deeper ribs

Guessing coil width
Always calculate based on profile development

Ignoring overlap
Overlap contributes to total width

Not matching machine tooling
Each roll forming machine may require specific coil width

Important Engineering Note

The exact coil width for an IBR profile cannot be confirmed without a profile drawing.

Small changes in:

• Rib geometry
• Overlap design
• Material thickness

can significantly affect the required coil width.

Always confirm using engineering calculations or supplier input.

How to Confirm the Correct Coil Width

To determine the correct coil width, you need:

Profile drawing (DXF or PDF)
Material type
Material thickness
Required cover width
Machine specifications

This ensures:

• Accurate production
• Reduced waste
• Correct machine setup

FAQ – IBR Coil Width

What happens if the coil width is too narrow?
The profile will not form correctly and ribs may be incomplete.

Why does IBR require more coil width than corrugated sheets?
Because of deeper ribs and more complex geometry.

Does thickness affect coil width?
Yes, thicker material increases bend allowance.

Can all IBR panels use the same coil width?
No, variations in design will change requirements.

Need Help Confirming Your Coil Width?

Incorrect coil width can lead to production issues, material waste, and higher costs.

Machine Matcher can help you:

Review your profile drawing
Calculate exact coil width and development
Match the correct roll forming machine
Advise on materials and setup

Contact our team to ensure your production is accurate and efficient from the start.