How to Specify a Corrugated Roofing Profile (Complete Guide)

Learn about how to specify a corrugated roofing profile (complete guide) in roll forming machines. Profile Guide guide covering technical details

Complete Engineering & Procurement Guide

Corrugated roofing is used worldwide in:

• Residential housing

• Agricultural buildings

• Industrial sheds

• Emerging markets

• Low-cost housing

It is one of the oldest metal roofing forms.

But corrugated is not universal.

The key variables are:

• Pitch (distance between waves)

• Depth (wave height)

• Radius shape

• Cover width

• Number of corrugations

These must be defined precisely before tooling.

1️⃣ What Defines a Corrugated Profile?

Corrugated profile is defined by:

Wave shape repeated across sheet width.

Critical dimensions:

• ✔ Pitch (center-to-center distance of waves)
• ✔ Depth (peak to valley height)
• ✔ Radius of curve
• ✔ Number of waves
• ✔ Effective cover width

Without these, the profile cannot be engineered.

2️⃣ Common Global Corrugated Standards

Different countries use different common geometries.

🇺🇸 USA – 2½" Corrugated

• Pitch: 2.67" (approx. 68 mm)

• Depth: ½" (13 mm)

• Cover width varies

🇬🇧 UK – 3" Corrugated

• Pitch: 76 mm

• Depth: ~18 mm

🇦🇫 Africa – 76/18

• 76 mm pitch

• 18 mm depth

• Very common export profile

🇦🇺 Australia – Custom Orb

• 762 mm cover

• Specific proprietary geometry

Never assume corrugated means same geometry globally.

3️⃣ Finished Dimensions to Specify

Before tooling approval, confirm:

• ✔ Pitch (mm or inches)
• ✔ Depth (mm or inches)
• ✔ Effective cover width
• ✔ Overall formed width
• ✔ Number of waves
• ✔ Edge detail (flat edge or full wave)

Small differences change developed width significantly.

4️⃣ Typical Coil Width

Corrugated coil width depends on:

Pitch × number of waves + edge allowance.

Example:

• 76 mm pitch × 10 waves
• = 760 mm
• Add edge allowance → 800–900 mm coil

Common coil widths:

• 914 mm

• 1000 mm

• 1200 mm

• 1250 mm

Corrugated usually uses narrower coil than PBR or R-panel.

Exact developed width must be calculated.

5️⃣ Thickness Range

Corrugated is often used in lighter gauges.

Typical thickness:

Residential / Emerging markets:

• 0.30–0.40 mm

Agricultural:

• 0.40–0.50 mm

Industrial:

• 0.50–0.70 mm

Thicker corrugated increases forming force significantly.

Machine must support:

Maximum thickness + maximum grade.

6️⃣ Material Grade

Common grades:

G250
G350

G550 possible but less common for shallow corrugated.

Higher grade increases:

• Springback
• Forming load
• Motor requirement

Grade must be defined before machine design.

7️⃣ Coating Type

Common coatings:

• Galvanized (Z coating)
• Galvalume (AZ coating)
• Prepainted

Corrugated often used in:

Coastal environments → require AZ coating.

Agricultural environments → corrosion resistance critical.

Coating type impacts roll finish requirement.

8️⃣ Radius & Wave Shape

Corrugated wave is curved, not angular.

Wave radius must be defined.

Large radius = smoother appearance
Small radius = tighter wave

Radius influences:

• Developed width
• Forming load
• Aesthetic performance

Never approximate radius during tooling design.

9️⃣ Edge Detail Specification

Edges can be:

• ✔ Half wave
• ✔ Full wave
• ✔ Flat edge

Edge detail impacts:

• Overlap
• Water tightness
• Installation alignment

Specify clearly.

🔟 Overlap & Fastener Method

Corrugated commonly overlaps:

One full wave.

Specify:

• ✔ Side lap configuration
• ✔ Fastener spacing
• ✔ Sealant requirements

Incorrect overlap causes leakage.

1️⃣1️⃣ Machine Engineering Requirements

Typical corrugated line:

• 10–16 forming stands

• 60–75 mm shafts

• 11–18.5 kW motor

• Hydraulic stop cut

Because corrugated has gradual forming:

Forming load is usually lower than trapezoidal profiles.

However, deep corrugated increases stand requirement.

1️⃣2️⃣ Production Speed

Corrugated lines often run:

20–40 m/min

Because forming geometry is smooth.

Cutting system choice determines maximum speed.

1️⃣3️⃣ Tolerance Requirements

Typical tolerance:

• Width ±2–3 mm
• Depth ±1 mm
• Length ±2–5 mm

Because corrugated often used in low-cost markets, tolerance expectations vary.

Export markets may require tighter control.

1️⃣4️⃣ Climate & Structural Considerations

Shallow corrugated:

Lower structural capacity.

Not suitable for:

High snow load
High wind zone

Deep corrugated improves strength but increases forming complexity.

Always match geometry to climate.

1️⃣5️⃣ Developed Width Reminder

Developed width calculation must include:

• ✔ Wave arc length
• ✔ Bend allowance
• ✔ Thickness compensation
• ✔ Springback correction

Corrugated arc geometry makes calculation slightly more complex than trapezoidal.

Never approximate.

1️⃣6️⃣ Export Variations

African 76/18 is extremely common.

Latin America uses various pitches.

Australia uses proprietary shapes.

Always confirm market standard before tooling investment.

1️⃣7️⃣ Common Specification Mistakes

• ❌ Saying “standard corrugated”
• ❌ Not specifying pitch
• ❌ Not specifying depth
• ❌ Ignoring wave count
• ❌ Guessing coil width
• ❌ Not checking structural suitability

Most corrugated tooling errors begin here.

1️⃣8️⃣ Final Corrugated Specification Checklist

Before tooling or machine approval:

• ✔ Pitch defined
• ✔ Depth defined
• ✔ Wave radius defined
• ✔ Wave count defined
• ✔ Effective cover width defined
• ✔ Edge detail defined
• ✔ Thickness range defined
• ✔ Grade defined
• ✔ Coating defined
• ✔ Developed width calculated
• ✔ Coil availability confirmed
• ✔ Climate suitability reviewed

Only then proceed to production.

FAQ Section

Is corrugated the same worldwide?

No — pitch and depth vary by region.

What is the most common export corrugated?

76/18 profile is very common globally.

Does corrugated require fewer stands?

Usually yes, due to smooth geometry.

Can corrugated run high speed?

Yes, often 30–40 m/min.

Is corrugated good for high wind zones?

Shallow versions are not.

Can I change wave count easily?

No — tooling must match exact wave geometry.