EB double wall vs C flute: side-by-side numbers

C flute is 17% thinner than EB double wall (0.156 vs 0.188 in nominal). At the same ECT, the McKee formula rates a C flute box 9% weaker in compression; the trade is in size, crush resistance and print surface.

Side by side

EB double wall is 0.031 in thicker than C flute. On a 12 × 10 × 8 in box that makes the outside 0.06 in longer and wider and 0.09 in deeper, and at the same ECT the McKee estimate for C flute is 91% of the EB double wall figure.

EB double wallC flute
Wallsdoublesingle
Nominal caliper, in0.18750.1563
Flutes per foot—39
OD added to L and W, in0.3750.313
OD added to depth, in0.5630.469
McKee strength index, same ECT43.339.5

Same box, both boards

Inside, inBCT at 44 ECT, EBBCT at 44 ECT, CBoxes per pallet, EBBoxes per pallet, C
10 × 8 × 6671613144144
16 × 12 × 108377644040
24 × 18 × 181,02593666

44 ECT is used on both sides only to isolate thickness; in practice the two boards are made to different grades. Pallet: 48 × 40, loaded to 60 in, column stacked.

Where each fits

EB double wall

  • Thinner than BC, so lower McKee strength at the same ECT
  • Smooth E face for printing
  • Slimmer outside dimensions than BC for the same inside size

C flute

  • Thicker than B, so stronger in McKee at the same ECT
  • Fewer flutes per foot than B, so slightly less crush and puncture resistance
  • Print surface is fine for simple marks; fine graphics prefer finer flutes

More comparisons

Sources