82 ECT EB double wall: box compression and stacking table

82 ECT EB double wall pairs a 82 lb/in edge crush with a nominal 0.188 in caliper. As an empty 12 × 12 × 12 in box, the simplified McKee formula puts it near 1,444 lbf of top-to-bottom compression before any allowance for storage or humidity.

Compression, derated for storage time

BCT after storage losses, lbf, 82 ECT EB double wall
Inside size, in	0 days	10 days	30 days	90 days	180 days
8 × 6 × 4	1,103	695	662	607	551
10 × 8 × 6	1,251	788	750	688	625
12 × 12 × 12	1,444	910	866	794	722
14 × 10 × 8	1,444	910	866	794	722
16 × 12 × 10	1,560	983	936	858	780
18 × 12 × 12	1,614	1,017	969	888	807
18 × 18 × 18	1,769	1,114	1,061	973	884
20 × 16 × 14	1,769	1,114	1,061	973	884
24 × 18 × 18	1,910	1,203	1,146	1,051	955
24 × 24 × 24	2,042	1,287	1,225	1,123	1,021

0 days is the McKee estimate itself. Storage losses are Packgent's default assumptions (10 days 37%, 30 days 40%, 90 days 45%, 180 days 50%), not sourced values; edit them in the stacking calculator.

How many high can it stack?

Boxes high, including the bottom one, column stacked for 30 days, before humidity, interlock or overhang losses.

12 × 10 × 8 in, BCT ≈ 1,383 lbf
Gross weight per box	10 lb	20 lb	30 lb	40 lb	60 lb
Boxes high	83	42	28	21	14

16 × 12 × 10 in, BCT ≈ 1,560 lbf
Gross weight per box	10 lb	20 lb	30 lb	40 lb	60 lb
Boxes high	94	47	32	24	16

20 × 16 × 12 in, BCT ≈ 1,769 lbf
Gross weight per box	10 lb	20 lb	30 lb	40 lb	60 lb
Boxes high	107	54	36	27	18

Boxes high = ⌊BCT × (1 − 0.4) ÷ gross weight⌋ + 1. A real stack needs further allowance for humidity, pattern and handling.

Neighbouring grades

Grade	ECT change	BCT change, same flute and size
71 ECT	-11 lb/in	-13%

In McKee, BCT scales directly with ECT, so the percentage change in strength equals the change in ECT.

Freight rule limits

NMFC Item 222 ties each grade to a maximum gross weight and size for LTL shipping. Packgent has not published those limits yet because they could not be checked against the current tariff. See the Item 222 page for status.

Sources

TAPPI T 811: Edgewise compressive strength of corrugated fibreboard (short column test)
McKee, R.C., Gander, J.W. & Wachuta, J.R. (1963). "Compression strength formula for corrugated boxes." Paperboard Packaging 48(8): 149–159
Flute calipers: Foster (1997), Wiley Encyclopedia of Packaging Technology

Last reviewed 2026-10-27. See all sources and how Packgent computes.