Understanding the Structure of Double Wall Corrugated Board
Inside double wall board: two flutes, three liners, and twice the strength.
Double wall structure
Quick answer
Double wall board has five layers: outer liner, outer flute, middle liner, inner flute, and inner liner. The two fluted layers each absorb impact independently, providing roughly twice the cushioning and compression resistance of single wall. The three liner papers resist puncture from both inside and outside. BC flute combination (approximately 7mm total) is the standard, with the B-flute outer providing a smooth printing surface and the C-flute inner providing maximum cushioning.
Layer functions
The first line of defence and brand surface.
Good printing support and puncture resistance.
Connects the two fluting layers.
Thicker flute absorbs more impact energy.
Protects contents from flute contact.
Flutes: flute types or weight limits.
How the structure creates strength
Two independent fluting layers each compress on impact, absorbing energy sequentially. Three liner papers distribute force and resist puncture. The combined structure is not simply twice as strong as single wall but provides roughly 2-2.5x the compression resistance due to the synergistic effect of the middle liner connecting the two fluting layers.
Double wall corrugated boxes
Engineered strength from ProcuraPack.
Browse double wall boxesFrequently asked questions
Five: outer liner, outer flute, middle liner, inner flute, inner liner.
BC combination is approximately 7mm.
Roughly 2-2.5x due to the synergistic middle liner effect.
BC: B-flute outer, C-flute inner.
B-flute outer for printing and puncture. C-flute inner for cushioning.
Part of our guide
Product Guide: Double Wall Cardboard Boxes
Expert guides on double wall cardboard boxes for heavy-duty shipping and industrial packaging.
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