Warehouse storage systems should be selected around the goods moving through the building, not capacity figures alone. A system that stores more pallets may also require specialist trucks, restrict access to individual loads, or complicate replenishment. Start by mapping inventory, order patterns, handling equipment and the route from receiving to dispatch. Then compare systems for storage density, selectivity, stock rotation, safety and total operating demands. Selective pallet racking suits broad access; deep-lane systems can use space more intensively but trade away some access. The right balance depends on what you store, how often it moves and how reliably staff can work within the planned layout.
Before comparing rack types, build a practical picture of the work the storage area must support. Count the number of active stock-keeping units (SKUs), estimate how many pallets or cases are held for each, and identify which items move frequently. A warehouse with many SKUs and only a few pallets of each has different needs from one holding a large quantity of a smaller product range.
Look beyond average demand. Consider seasonal peaks, replenishment frequency, order-line sizes, returns and any products that need separate handling. If staff regularly pick individual cases from pallet stock, the design must account for both reserve storage and the forward picking locations from which orders are assembled. A system that fits bulk stock but makes picking awkward may shift the bottleneck to replenishment or order fulfilment.
Record the dimensions and weights of pallets, containers and long or irregular items. Include the full load, not just the product. Then identify the equipment that will access the storage: counterbalance or reach trucks, order pickers, pallet trucks, conveyors or automated equipment. Truck turning and lifting requirements influence aisle layout, rack height and the type of pallet position that can be used safely.
Use these details to define what “efficient” means at your site. It may mean direct access to each pallet, fewer forklift movements, more pick faces or room to handle seasonal stock. Those priorities can conflict, so agree on the important ones before requesting a design.
The options below address different combinations of density and access. The stated stock rotation describes a typical configuration; the actual arrangement should be confirmed in the system design and operating process.
| System | Access and stock rotation | Often suits | Main trade-off |
|---|---|---|---|
| Selective pallet racking | Direct access to each pallet; supports varied stock rotation practices. | Many SKUs, mixed inventory and frequent selection of individual pallets. | Access aisles take space, so storage density is lower than in many deep-lane layouts. |
| Double-deep racking | Two pallet positions deep; rear pallets are less directly accessible. | Higher quantities per SKU where some selectivity can be exchanged for density. | Needs suitable handling equipment and can add moves to reach rear loads. |
| Drive-in or drive-through racking | Forklifts enter storage lanes; drive-in commonly operates on a last-in, first-out basis, while drive-through can support first-in, first-out when access and controls are arranged for it. | Large, relatively uniform quantities of the same product. | Access to an individual pallet is limited within a lane; truck movement inside the structure needs careful control. |
| Push-back racking | Multiple pallets occupy a lane; loading and retrieval typically follow last-in, first-out. | Several pallets per SKU when more density than selective racking is needed. | Not suited to every stock rotation requirement, and the lane must be managed as a sequence. |
| Pallet-flow racking | Pallets move through a lane on rollers; a correctly managed layout can support first-in, first-out. | High-throughput stock with enough volume to keep lanes productive. | Requires compatible loads and disciplined replenishment; system components need appropriate maintenance. |
| Shelving or carton-flow storage | Goods are accessed by hand; carton flow can present replenished items at a picking face. | Small items, piece picking and case-pick zones. | Less suitable for storing heavy pallet loads, and pick faces need replenishment planning. |
| Cantilever racking | Open-front arms provide access to long or awkward loads. | Timber, pipe, profiles and other goods that do not fit well on standard pallet beams. | Load dimensions, support points and handling methods need to match the design. |
| Automated storage and retrieval systems | Machines store and retrieve loads within a designed system. | Operations with suitable, repeatable loads and a case for automation across the workflow. | Higher integration and planning demands; equipment, software and operating processes must work together. |
Selective racking is often a useful starting point when the warehouse must reach many different pallets without moving other stock first. It is not automatically the best choice for every operation: where a few SKUs occupy many positions, deep-lane storage may use the available footprint more effectively. Conversely, a high-density layout can be a poor fit when orders require frequent access to the rear pallet or when stock rotation must be tightly controlled.
Density is only useful if goods can be put away and retrieved at the pace the operation needs. Deep-lane systems reduce the number of access aisles compared with arrangements that provide direct access to every position, but that can also mean more restricted selection. If an operator must move other pallets to reach a required load, the apparent space saving may come with extra handling and delay.
Consider the relationship between storage and picking. Bulk reserve stock might sit in a dense area while frequently picked cases are held in shelving or carton-flow locations closer to the work area. This separates storage for full loads from the locations used to assemble orders. It can reduce repeated travel through reserve lanes, but it also adds replenishment tasks that must be planned and monitored.
Material flow matters across the whole building. Receiving, checking, put-away, replenishment, picking, packing and dispatch all need workable routes and enough space to perform their tasks. If a storage design blocks a natural path between these activities, congestion can build at aisle ends, staging areas or shared crossings. Assess the proposed layout using actual operating movements, including busy periods, rather than looking only at a rack plan.
Standard pallet racking works best when loads are sufficiently consistent for the planned beam levels and handling equipment. Pallets that vary in height, have unstable wrapping or overhang their base can make a nominally efficient layout difficult to use. Allow for the actual load profile and confirm how unusual or non-standard loads will be stored rather than assuming every pallet fits the same position.
Small products need a different access strategy. Shelving can support hand picking across a wide range of items, while carton-flow lanes can bring replenished stock toward a picking face. For either approach, consider how staff will replenish locations without disrupting picking, and whether the arrangement gives clear identification of each item.
Long or bulky products may need cantilever racking or another purpose-designed support arrangement instead of conventional pallet beams. The important checks include load length, weight distribution, support points and the equipment used to place and retrieve each item. A storage system should be designed for the real load and handling method, not adapted informally after installation.
Automated storage and retrieval can reduce some manual travel and provide controlled handling, but it is a system decision rather than a stand-alone rack choice. The business must consider the goods it can handle, the work the equipment will perform, software and control requirements, maintenance arrangements and what happens if part of the system is unavailable. Compare the full operating model with the manual alternative before committing.
Rack height and aisle arrangement depend on the building as well as inventory. Check clear height, columns, doors, lighting, sprinklers and other fixed services against the proposed rack positions. Also confirm floor conditions and the design requirements for the loads, rack configuration and equipment. A plan that looks efficient on a drawing may not be usable if it conflicts with building features or leaves too little room for handling tasks.
Aisle width should be chosen with the intended trucks and their working clearances in mind. Narrower aisles may increase the area available for storage, but they are not a safe shortcut if the selected truck cannot turn, place loads or operate as intended within them. Confirm the equipment specification and layout together. If the plan depends on new or different equipment, include that requirement in the decision and cost assessment.
Plan staging and access areas alongside storage positions. Receiving and dispatch need room for the work assigned to them; pick and pack areas need to connect sensibly with the stock they serve. Keep pedestrian routes and vehicle movements visible in the layout, and consider how staff will handle exceptions such as damaged goods, returns or loads that cannot be put away immediately.
For a New Zealand site, confirm applicable building, fire-protection and structural requirements with qualified local professionals. Where seismic design is relevant, include it in the review of the rack and its connections to the building or floor. Requirements depend on the site and proposed system, so a supplier’s rack layout should not be treated as a substitute for whole-site compliance checks.
Compare more than the purchase price. The project may involve racks, installation, handling equipment, floor or building work, protection, signage, software, training and changes to picking or replenishment processes. High-density options can also require more specialised equipment or tighter operating controls. Ask for the assumptions behind each proposal so that alternatives can be compared on the same basis.
Safety planning should cover load limits, equipment movement, pedestrian routes and the condition of the storage structure. The design must reflect the intended loads and configuration, and staff need clear procedures for using the system. Establish how damage will be reported, assessed and addressed; if a rack is struck or visibly damaged, do not treat continued use as routine without an appropriate assessment.
Maintenance needs vary by system. Flow components, automated equipment and control systems have different service requirements from conventional racking. Before choosing a more complex arrangement, identify who will maintain it, how issues will be reported and how work will continue if equipment or a lane is temporarily unavailable. These practical arrangements affect the system’s usefulness as much as its theoretical capacity.
Ask each supplier to explain what the design assumes about pallet consistency, stock rotation, access equipment and daily operating practices. If two proposals claim different storage capacities, check whether they use the same inventory, aisle and handling assumptions. Capacity figures are only comparable when their underlying layouts and workflows are comparable.
Deep-lane options such as drive-in, push-back and pallet-flow systems can store more loads within a given area than layouts with an aisle serving every position. The best fit depends on SKU quantities, access needs, load characteristics and stock rotation. Compare usable capacity with the handling steps the system requires.
It can be suitable when the operation needs direct access to many different pallets, but the aisle layout still determines how much floor area remains for storage. A small site should also account for staging, picking and safe equipment movement. Compare the usable layout, not just the number of rack positions.
Start with the way inventory must be rotated and managed. FIFO means the first load placed is the first one retrieved; LIFO means the most recently placed load is retrieved first. The product, stock-control process and lane design all matter, so confirm that the selected system supports the required sequence in day-to-day operation.
Yes. A facility may use pallet racking for reserve stock, shelving or carton flow for piece picking, and a separate arrangement for long or awkward loads. Multiple systems can match different goods and tasks, but their locations and replenishment routes need to work as one layout.
Confirm the loads and rack configuration, building constraints, handling equipment, floor and structural requirements, access routes and applicable fire-protection requirements. Set procedures for operating and inspecting the system, including how damage is reported and assessed. Use qualified professionals for site-specific design and compliance questions.
The strongest warehouse storage plan is the one that supports the inventory and work the facility actually handles. Compare each option for density, access, stock rotation, equipment fit, safety and whole-life operating demands, then test the layout against real receiving, picking and dispatch movements before approving the design.
