Pallet Stacking Patterns: Column, Brick, Pinwheel and Split-Row Compared

A pallet pattern decides two things at once: how the load will hold together in storage and transit, and what the palletizer has to do to build each layer. Most pattern guides cover the first. This one compares the four common pattern families on both, so you can shortlist a pattern before asking palletizer suppliers how they would form it.

It is a comparison compiled from published research and manufacturers’ public information. Stability and strength statements are qualitative. The verification requirements are collected in Limits and verification.

“Forming effort” below is an editorial inference, not a measured rate. Use the blank layer and acceptance record to compare actual layouts.

What do the four pattern names mean?

The four names describe how cases are oriented within a layer and how each layer sits on the one below. A column pattern repeats the same layer so cases stand corner on corner. Brick, split-row and pinwheel patterns change orientation or offset from layer to layer so that cases bridge the joints below. The names themselves are not standardized: a 2017 Virginia Tech thesis on pallet stacking patterns notes that commercial palletizing software packages use their own names and groupings. Published pattern guides apply “brick” especially loosely, to anything from offset rows to any interlocked layout. The definitions below are the ones this guide uses. When you talk to a supplier, exchange layer drawings rather than names.

The thesis tested column, split-row and pinwheel patterns, plus hybrids with column-stacked bottom layers and interlocked upper layers. The patterns came from the commercial software CAPE and BestLoad. A hybrid is a candidate to assess, not a proven combination for another case or pallet.

Takeaway: Exchange odd/even layer drawings; a pattern name alone cannot establish joint bridging.

Column or interlocked: what is the trade-off?

A column stack uses the strongest part of a corrugated case, the corners, but the layers are not tied together. An interlocked pattern ties the layers together but loads the weaker walls of the cases below. Every pattern on this page sits somewhere on that trade-off.

The Virginia Tech thesis summarizes earlier research on both sides:

• Strength. A stacked case carries most of its load at the corners. Interlocking shifts load from the corners to the walls. The studies summarized there estimate the loss in load-carrying capacity at 35% to 55%, depending on the conditions of each study. Treat this as the size of the effect, not a design factor for your case.
• Stability. In an interlocked pattern, each layer holds the cases below it in place by pressing in the opposite direction. Column stacks tend to produce unstable loads that need containment such as stretch wrap, stretch hood, strapping or tie-sheets. Interlocking combined with containment increases overall stability.
• The catch. If interlocking weakens the cases enough that the bottom layer fails, the whole load can become unstable. An interlocked pattern does not make a load safe if the case was sized for column stacking.

The thesis also cites three criteria for judging how stable a pattern is without containment, from Carpenter and Dowsland (1985):

1. Each case should be supported by at least two cases below it.
2. A high percentage of each case’s base should be in contact with the layer below.
3. The pattern should avoid continuous vertical “cuts” that split the load into independent columns.

In the thesis’s own test load, each case in the upper layers of the column pattern rested on one case, while in the fully interlocked split-row and pinwheel patterns each case rested on 2.7 cases on average. The column pattern had seven continuous cuts across the load, and the others had one. These numbers belong to that case and pallet size, but they show how the criteria separate patterns. The thesis did not test a brick pattern. Offsetting rows that all run the same way removes continuous cuts in one direction only, so a load that needs joints bridged in both directions usually needs a split-row or pinwheel layout. Check any candidate against the criteria with the real case size.

Takeaway: Review bottom-case loading before choosing interlock for its stability benefit.

How do the four patterns compare?

Column stacking keeps the most case compression strength without layer interlock, so stability comes from containment. Brick, split-row and pinwheel patterns trade some compression strength for interlock and ask the palletizer to turn or arrange more cases. The opening comparison is qualitative and relative to column stacking. “Forming effort” reflects what the palletizer must do, based on the layer definitions above, not a measured rate.

Space use is not in the table because it depends on the case and pallet dimensions, not on the pattern name. For a given case size, one pattern may fill the pallet deck with no overhang while another cannot. Pattern software is used to find layouts that fill the deck. The thesis selected only patterns with full deck coverage, no overhang and no internal gaps.

Takeaway: Compare deck coverage and case support using the actual dimensions, then assign the forming sequence.

How does a palletizer form each pattern?

The pattern becomes a machine requirement once you ask how the cases will be turned, grouped and placed. Conventional (layer-forming) palletizers build a whole layer and then transfer it. Robotic palletizers place one case, a group or a row at a time. Each type turns cases differently, so the same pattern can be easy for one and slow for the other.

Conventional layer-forming palletizers

BW Packaging describes this sequence on its Maximizer high-speed case palletizer:

• A metering belt creates a controlled gap between incoming cases.
• Multi-lane dividers position the cases.
• Cushioned overhead turners rotate cases to suit different patterns.
• Full-width pivoting case stops square the cases into a layer in an accumulation area.
• A pusher bar moves the layer onto bi-parting transfer plates, which set it on the load.

Supplier material for Scott’s NexPAL 200HL (Packaging World, September 2026) describes a side-mounted rotating row pusher that lets case infeed and row formation happen at the same time.

On this kind of machine, every case that has to change orientation passes through a turner. Patterns with more turned cases per layer, such as pinwheel, ask more of the turner and the row-forming sequence than a column or brick pattern. Ask the supplier whether your pattern can be formed at your target case rate, and how many turning positions it needs.

Robotic palletizers

A robot turns cases with its wrist, so orientation changes come from the program rather than from a turner. Suppliers describe patterns as recipes. ELCAT (supplier-submitted, Packaging World, October 2026) describes cases placed according to a palletizing recipe, with vacuum or mechanical grippers and single or multiple case picking. Applied Manufacturing Technologies (supplier-submitted, Packaging World, September 2026) describes entering case dimensions and selecting a pattern on its cobot palletizer interface.

Picking a whole row is also possible. In a 2015 Packaging Digest plant report, the robot used a fork-style gripper to remove a row of typically three to five cases from the infeed. A robot’s rate depends partly on how many cases it can take per pick in the chosen pattern, and a pattern that needs several orientations can force single-case picks, so ask the supplier how many picks per layer each candidate pattern needs.

Pattern changes are part of format changes. In a 2026 Packaging World report, Boxed Water sends its palletizing system supplier the case dimensions and pallet patterns for each new format, and the supplier updates the palletizer on site or remotely. Treat a new pattern like any other recipe change, as described in the format changeover checklist, and see the PLC, HMI and motion control guide for where recipes sit in a control system.

Takeaway: Ask for turns and picks per layer, including gripper approach and release, for every shortlisted drawing.

What containment does each pattern need?

Containment is decided together with the pattern, not after it. Plan containment from the complete load; neither the column nor the interlocked pattern name sets a universal requirement or wrap force. The thesis lists stretch wrapping, stretch hooding, strapping and shrink wrap as containment methods, and names stretch wrap as the most common. It notes that wrapping can be manual, semi-automatic or automatic, with automatic machines receiving the load from a conveyor.

Sheets between layers are part of the same decision:

• Slip sheets or tie-sheets. In the Packaging Digest report, the robot placed a slip sheet between layers automatically. The first sheets were too thin for the robot to pick, and a thicker sheet solved it. If you use sheets, their specification is a machine input.
• Sheet dispensing. ELCAT lists interlayer sheet management in its more automated configurations. Confirm whether sheet handling is in the palletizer scope or supplied separately.

Too much containment force can also damage packages, as the thesis notes. That is one reason the wrap specification should be tested on the chosen pattern rather than copied from another product.

Takeaway: Include sheets and containment in the same acceptance record as the pattern.

How should you choose a pattern?

Start from the case and the shipping conditions, shortlist one or two patterns, then let the palletizer supplier show how it would form them. A pattern that looks best in software can still fail on compression, stability or forming rate.

As a starting rule: if the case was designed for corner loading and has little compression margin, start with a column pattern and plan containment and sheets around it. If the case has margin for an interlocked pattern and the load needs to hold together with less containment, compare split-row and pinwheel layouts that bridge joints in both directions. If the case is weak at the bottom layers but the top of the load needs stability, consider a hybrid with column-stacked bottom layers and interlocked top layers, as tested in the thesis. These are candidate-selection rules; verification is covered below.

Inputs to collect first. Soontrue’s list of information needed for a robotic palletizing project covers most of them:

• Case length, width, height and weight, and whether the case is designed for column or interlocked stacking.
• Pallet dimensions and any customer pallet or overhang rules.
• Target stack height and number of layers.
• Case rate from the line, and whether it varies by SKU.
• Conveyor height, case orientation and spacing as the cases arrive.
• Containment method and whether slip sheets or tie-sheets are used.
• Available floor space.

Steps:

1. Generate candidate layouts in pattern software for the case and pallet, keeping only those with full deck coverage and no overhang, unless overhang is accepted.
2. Check each candidate against the three stability criteria above and against the case’s compression design. If the case was designed for column stacking, an interlocked pattern needs a case strength review.
3. Ask each palletizer supplier how it forms the shortlisted patterns, including turning, picks per layer and the rate it can sustain.
4. Specify containment and sheets for the chosen pattern.
5. Test a full load with the real cases, pattern and containment under the handling and transport conditions you expect, then record the result in the acceptance plan.

As the last machine in the line, the palletizer can become the constraint when upstream output rises, a point made in both Soontrue’s WP30 material and Scott’s NexPAL release. The bottleneck guide shows how to check whether it is.

Copyable layer and acceptance record

Copy one record per candidate; attach an odd/even drawing with a defined origin and units. For each case position, record the case ID, x/y coordinates and orientation. The blank rows below are a layer-map record, not a calculated layout.

For a central gap, retain its dimensions and the support area around it. For a hybrid, record the exact bottom/top layer sequence and assess the transition. For a gripper restriction, request a demonstration of approach, release and case placement for that drawing. These are checks to resolve with the project team, not automatic exclusions.

Takeaway: Keep the layer drawing and the machine demonstration under the same revision before accepting the load.

Questions for palletizer suppliers

• Can the machine form each shortlisted pattern at the target case rate? Please state the rate for each pattern separately.
• How are cases turned (turner, robot wrist), and how many turns does each layer of each pattern need?
• How many picks per layer does each pattern need, and can the gripper take rows or groups?
• How is a new pattern created and loaded, and who can do it: operators, maintenance or only the supplier? Is remote update possible?
• Are slip sheet or tie-sheet dispensing, pallet dispensing and stretch wrapping in scope, and what sheet specification does the machine need?
• What infeed conditions does the palletizer need: case orientation, spacing, conveyor height and the signals from upstream equipment? The line integration checklist lists the interfaces to assign.
• How will pattern accuracy and load quality be checked at factory and site acceptance? See the FAT and SAT guide.

For the case packing and sealing steps that feed the palletizer, see the cartoner and case packer comparison.

Takeaway: Carry each open forming, support or containment question into FAT/SAT with a named owner.

Limits and verification

This comparison describes general tendencies. It cannot tell you whether a specific load is stable or strong enough:

• The compression loss range comes from earlier studies with their own cases and conditions. It shows the direction and rough size of the effect, not a value for your case.
• The pallet deflection results in the thesis showed that interlocking reduced pallet deflection by up to 53%, but only under the support conditions where deflection was large. The author states that the results are not an adjustment factor for industry use.
• Forming effort in the comparison table is derived from the layer definitions and manufacturer descriptions. The supplier’s demonstration with your cases is the evidence.
• Stability depends on case, pattern, sheets and containment together. Test full loads under the handling and transport conditions you expect before releasing a pattern.
• Storage, handling and transport rules vary by customer and market, and this guide does not cover them.

Frequently asked questions

What is the correct way to stack cases on a pallet?

There is no single correct pattern. Column stacking keeps case compression strength but needs containment. Interlocked patterns add stability at the cost of compression. Choose from the case design and shipping conditions, then test the full load.

How do you correctly layer product on a pallet?

Fill the pallet deck without overhang where possible, support each case on at least two cases below if the pattern is interlocked, avoid continuous vertical splits, and add slip sheets and containment as the load requires. Check the result with a full-load test.

How is gripper count determined?

Adapted from the Q&A in iNexBot’s public palletizing-process manual: its configuration distinguishes tools that pick or place separately from those acting together. Ask the palletizer supplier to record the actual group size, approach/release clearance and picks per layer for your drawing; the controller’s gripper count alone does not prove the pattern can be formed.

Method and sources

This guide compares pattern families using one third-party research source, a Virginia Tech thesis that also summarizes earlier studies, together with manufacturers’ and trade media’s public descriptions of palletizers. The pattern definitions are our own, because published names differ. “Interlock” here means geometric joint bridging: the pinwheel arrangement within one layer does not itself demonstrate lateral restraint, friction or acceptable load strength. The new layer record is an editorial worksheet, not a load-design standard. Strength and stability statements are qualitative or are attributed to the study that produced them. Forming effort is an inference and is labeled as such. In a search of US desktop results for “pallet stacking patterns” on October 7, 2026, the top results were general warehouse stacking guides, pattern charts and calculators, without a comparison that connects patterns to how a palletizer forms them.

Original sources accessed October 7, 2026. The added gripper question was checked October 8, 2026 against iNexBot’s public palletizing-process manual, Q&A and gripper settings. It describes that implementation, not every palletizer.

Sources:

• Eduardo Molina Montoya, “Investigation of Pallet Stacking Pattern on Unit Load Bridging”, M.S. thesis, Virginia Tech, May 2017.
• BW Packaging, “BW Packaging Maximizer Series High-Speed Case Palletizer”, product page.
• Jack Mans, “Heavy duty palletizing”, Packaging Digest, March 12, 2015.
• Packaging World, “Boxed Water Brand Hands Heavy Case Stacking to Robotics”, July 2, 2026.
• Packaging World, “Scott Technology Addresses Factory Space Constraints with a Compact, High-capacity Palletizer”, supplier-submitted, September 23, 2026.
• Packaging World, “CRX-Based Collaborative Palletizing Solution”, supplier-submitted (Applied Manufacturing Technologies), September 25, 2026.
• Packaging World, “ELCAT Food Technology Introduces Three Levels of Robotic Palletizing Automation”, supplier-submitted, October 1, 2026.
• Soontrue, “WP30 Robotic Palletizing System: Automatic Carton Palletizing at Propak Cape 2026”, September 22, 2026.

For where palletizing sits in a complete line, see the overview of packaging machine types and the packaging automation guides.