Corrugated Board: Comprehensive Guide about Material, Types & Strength for Corrugated Boxes

Corrugated cardboard is commonly used to manufacture packing and shipping cartons. With availability of different types of corrugated boxes in the market, corrugated cardboard boxes are mostly considered as favourite packaging box where safety and protection of packed item is needed, especially in the long distance shipping. Light in weight and sturdy in packaging are the properties of corrugated board that makes it most favourite packing material. Corrugated boxes also offer durability, strength, recyclability and cost effectiveness and are considered great choice for brand awareness and marketing.

How Corrugated Board is made and Which Material is used?

flute types of corrugated boxes

In simple words, corrugated board is made from a corrugated inner medium called “flutes” sandwiched between two sheets of papers called “inners”. These layers of inners and flutes are structured to make a sturdier box with better strength than that of each definite layer.

corrugated box made with two layers of inners and a single layer of flutes is called “Single Wall Corrugated Box” while Double Wall and Triple Wall boards are available as well.

What Are Flutes and How Many Flute Types Are There?

Corrugated flutes are the letter S structured waves/spans that form the corrugated board. These flutes run parallel to deepness of the board and give the box its rigidity and stacking strength. Apart from providing strength, these flutes also provide insulation to packed items from sudden temperature swings.

Below you will find a chart for most commonly used flute types and their specification along with their advantages.

Flute TypesFlute per FootThicknessAdvantages
A Flute333/16″Greater strength and cushioning
B Flute42-501/8″Good cushioning, stacking & printing
C Flute39-4311/64″Good stacking, strength & crushing resistance
E Flute941/16″Great crush resistance & printing surface
F Flute1251/22″Greatest crush resistance & printing surface

What is Edge Crush Test?

The Edge Crush Test is a test method performed in laboratory to measure the “stacking” or “crushing” of a sample corrugated board. This test will dictate the potential compression and strength of the box made from sample board. Watch following video for a demonstration of ECT.

Below is a simple chart depicting the board type and their ECT score along with weight limit.

Types of ConstructionEdge Crush TestMaximum Suggested Load Capacity (lbs)

*Some Interesting Facts about Corrugated Boards

  • Around 43.9 billion m2 corrugated board produced every year almost enough to cover the area of Denmark
  • More than 40% of corrugated packaging is used to package food products
  • Corrugated packs and protects more than 75% of European goods
  • 88% of corrugated packaging is derived from recycled content
  • 100% recyclable and biodegradable


Need Corrugated Boxes?

Do you need corrugated boxes for storage or shipping purposes? Contact us today with your requirements and demands and one of our representatives will follow up with a solution and answers to your questions.

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