112 ECT AAC triple wall: box compression and stacking table

112 ECT AAC triple wall pairs a 112 lb/in edge crush with a nominal 0.531 in caliper. As an empty 12 × 12 × 12 in box, the simplified McKee formula puts it near 3,320 lbf of top-to-bottom compression before any allowance for storage or humidity.

Compression, derated for storage time

BCT after storage losses, lbf, 112 ECT AAC triple wall
Inside size, in	0 days	10 days	30 days	90 days	180 days
8 × 6 × 4	2,536	1,598	1,521	1,395	1,268
10 × 8 × 6	2,875	1,811	1,725	1,581	1,438
12 × 12 × 12	3,320	2,092	1,992	1,826	1,660
14 × 10 × 8	3,320	2,092	1,992	1,826	1,660
16 × 12 × 10	3,586	2,259	2,152	1,972	1,793
18 × 12 × 12	3,712	2,339	2,227	2,042	1,856
18 × 18 × 18	4,066	2,562	2,440	2,236	2,033
20 × 16 × 14	4,066	2,562	2,440	2,236	2,033
24 × 18 × 18	4,392	2,767	2,635	2,416	2,196
24 × 24 × 24	4,695	2,958	2,817	2,582	2,348

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 ≈ 3,179 lbf
Gross weight per box	10 lb	20 lb	30 lb	40 lb	60 lb
Boxes high	191	96	64	48	32

16 × 12 × 10 in, BCT ≈ 3,586 lbf
Gross weight per box	10 lb	20 lb	30 lb	40 lb	60 lb
Boxes high	216	108	72	54	36

20 × 16 × 12 in, BCT ≈ 4,066 lbf
Gross weight per box	10 lb	20 lb	30 lb	40 lb	60 lb
Boxes high	244	122	82	61	41

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
90 ECT	-22 lb/in	-20%

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.