The key to designing an efficient warehouse is setting up a racking system that optimises the available storage space, while at the same time facilitating the movement of people and goods around the facility. This usually requires a mix of different types of warehouse shelving. In this guide we will identify the different types of warehouse shelving systems along with their benefits and best applications.
In a practical sense there are 3 main categories of shelving that are relevant to setting up a warehouse racking system:
Pallet racking that is designed for the handling of palletized goods with forklifts and mechanical picking platforms
Industrial Shelving that is designed on a human scale for manual picking and handing
Specialist racking that is designed for special applications and odd shaped items
Set out below is a brief description of the various shelving and racking types that fall within each of these three categories.
2. Pallet Racking
Warehouse pallet racking is a type of shelving used for holding palletized goods. Palletizing goods makes sense as it makes handling, put away and picking so much easier.
Loaded pallets can be stored directly on the floor, either singly, one pallet high (floor stacking) or stacked one on top of another (block stacking). However, it is a much more efficient use of space to use pallet racking to store pallets.
Pallet racking is one of the most common warehouse storage systems. Essentially, it is a very heavy duty storage system that stores pallets of items in horizontal rows on multiple levels within a vertical, steel rack. The pallets are typically loaded onto the racks and unloaded with the aid of a forklift. This approach maximizes the use of the vertical space in the warehouse.
There are 3 main types of pallet racking:
- Selective Pallet Racking
- Drive-In & Drive Thru Pallet Racking
- Flow Racking
2.1 Selective Pallet Racking (static racking)
Selective pallet racking earns its name because you can “select” a pallet without having to move other pallets out of the way. It is the simplest and cheapest type of pallet racking and it works well with any type of forklift without the need for specialized lifting equipment.
This type of racking is most commonly designed to be 1 pallet deep (single deep), but if there are multiple pallets of the same item, then it can also be configured two pallets deep (double deep).
2.1.1 Single Deep
Unless specified otherwise, Selective Pallet Racking generally refers to single deep racking. Single deep selective racking is the most common type of warehouse racking for good reason. It is a very versatile warehouse storage solution; each pallet position can hold a different product SKU. Each pallet is easily visible and it allows direct access for loading and unloading at any time. This ease of access also makes damage less likely.
It is available in a range of heights and depths and changing the product mix being stored is just a matter of swapping out pallets. It is easy to install and dismantle and it is suitable for both fast and slow moving goods.
Selective pallet racking systems are easy to source and are inexpensive on a cost-per-pallet position basis. A standard forklift with tines is all that is required – no need for special attachments or lift trucks.
It is ideal in situations where there are a large number of different products with low volumes, different weights and sizes that have a low turnover or are perishable. It works well in a warehouse that uses a First-In, First-Out (FIFO) inventory system. This will suit industries such as manufacturing, retail, food and beverage and pharmaceuticals.
On the downside, it doesn’t provide the same density of storage as other systems and it requires numerous, wide aisles so that the forklifts can access and maneuver the pallets.
2.1.2 Double Deep Pallet Racking
Double deep or double reach racking shares the same components as single deep racking. The difference is that it’s twice as deep, so each position can accommodate two pallets one in front of the other. This modification increases the storage capacity of the warehouse space, by reducing the necessary aisle space. However, it does require a special, “double reach” forklift to maneuver the pallets at the back of each position.
It suits situations where there are multiple pallets of the same product being stored in-line, back-to-back and where the inventory is managed using a Last-In, First-Out (LIFO) system.
Double deep racking may cost a bit more to implement and reduce the variety of products that can be efficiently stored, but the trade off is the increased storage capacity that it offers. It suits applications such as general warehousing and manufacturing, retail and food and beverage warehousing.
2.1.3 Modified Pallet Racking
Standard pallet racking components can be used with some additional modified components to store odd shaped (ugly) items. This type of racking is often combined with different material handling vehicles or forklift attachments. Some of the common modified applications are described in the table below.
|Coil/ Drum Racking
- Storage of steel coils and drums
- Uses pallet racking uprights and beams with the addition of steel cradles to stop stored coils and drums from rolling
- Forklift is mounted with a drum racker
- Storage of cable drums or spindles
- A steel rod is positioned through the centre of the drum to place on brackets attached to the racking uprights
- Forklift has a special attachment for placing/ removing cable drums and spindles
- Storage of carpet and vinyl rolls
- Carpet racking is a deep racking system that allows for the storage of carpet rolls in a pigeon-hole style
- Forklift has a roll prong attachment
- Storage of sheet materials like gyprock, sheet metal, wood and plastics
- Uses pallet racking uprights and beams to create the correct sized locations
- Forklift has standard tines
2.2 Drive-in and Drive-thru Pallet Racking
Drive-in/Drive-thru racking is a high density storage system that does away with the horizontal shelves of selective racking and replaces them with ledges on the uprights. The left and right side of each pallet is supported on these ledges and the middle of the pallet is suspended in the air. In this way the space between the uprights is open and can be used as a lane that standard-tine forklifts can drive down to deposit a pallet at different heights on the available ledges.
The main advantage of this racking system is that it reduces the aisle space needed for storing stock and so significantly increases the storage capacity of the warehouse over a standard selective racking system.
For best effect, each lane should have low-medium turnover pallets that hold the same SKU’s. Thus it suits situations where there are many pallets of the same product being stored.
This type of racking comes in two variations drive-in and drive-thru.
2.2.1 Drive-In Racking
Drive-in pallet racking has only one access point at the front. Pallets are loaded and retrieved by a forklift driving into a lane to place or pick up a pallet that is up to 4 spaces deep. The forklift then needs to back out of the lane to maneuver around the warehouse.
This system works best for Last-In, First-Out (LIFO) operations, where the last pallet loaded becomes the most accessible pallet and so the first one to be taken out. It suits environments where the inventory turnover is not high and where the pallets are of uniform size and have relatively uniform loads. It doesn’t suit products that are perishable or have a short shelf life or are easily damaged.
2.2.2 Drive-Thru Racking
Drive-thru is essentially the same system as Drive-in racking except there is access from both the front and the back of each lane. Forklifts load the new pallets from the front and pick or unload the pallets they need from the back.
Because of the different loading and unloading positions, drive-through racking works best with First-In, First-Out (FIFO) storage operations, where many uniform pallets of the same product are being stored. For example: cold storage/ freezer rooms storing meat or flowers, beverage storage and chemical storage. It isn’t ideal for high turnover situations.
2.3 Flow racking (gravity flow racking)
Flow racking is a gravity-feed system, where the shelves slope down slightly from the back to the front. Rollers on the shelves allow pallets or cartons that are loaded at the back to roll forward under the effect of gravity. Items are then picked from the front, so it is ideal for a First-in, First-out (FIFO) system that involves perishable or seasonal items
It comes in two forms: pallet flow racking and carton flow racking.
2.3.1 Pallet Flow Racking
Pallet Flow Racking is a high-density, FIFO storage system, where a standard forklift loads pallets at the back of the racking and picks are unloaded from the front. It is the most expensive form of pallet racking, but it offers efficient high density storage.
The gravity feed system supports very high-density storage of up to 20 pallets deep in one lane. This minimizes the number of aisles needed, while still maintaining efficient inventory turnover. The system enhances the put-away and retrieval process, so reducing the amount of labour required. It is great where there are limited numbers of high turnover SKU’s in large volumes and where those products have an expiry date.
This system is widely used in perishable-goods warehouses. It works well in freezer warehouses, food distribution centres and grocery warehouses.
2.3.2 Carton Flow Racking (Carton Live Storage)
The same gravity-fed strategy can be used with smaller items, such as cartons and containers. Carton flow racks are designed specifically for small, non-palletized, lightweight items that need to be picked frequently and quickly.
Cartons are loaded at the back by hand and then unloaded manually from the front. Higher levels can be given over to a buffer of pallet flow type storage to take advantage of the vertical space above the hand picking area.
2.3.3 Push-Back Pallet Racking
Push back racking is a similar gravity-fed system to pallet flow racking except that pallets are loaded and unloaded by standard-tine forklifts from the front only. The way it works is pallets are loaded onto an inclined track and cart system that pushes any existing pallets backwards and upwards (2-6 pallets deep). When the second pallet is loaded onto the cart, it pushes the top cart with the first pallet to the back.
The last pallet stored thus becomes the first in line to be picked, so it suits LIFO based inventory systems. The pushing of pallets does have a higher risk of damage.
Like the other gravity-fed storage systems, it suits the storage of numerous pallets of the same SKU. Being a LIFO system it works better with faster moving products that have a longer shelf life. So it is great for frozen products in cold storage rooms.
3. Industrial Shelving
Industrial shelving is medium to heavy duty shelving that is suitable for hand loading and picking. It can be used by itself in a warehouse installation or mixed with pallet racking to support your picking processes and optimize efficiency in any industrial space.
The main types of industrial shelving are:
- Long span shelving
- Rivet shelving
- Wire shelving
- Mobile shelving
- Steel shelving
3.1 Long Span Shelving
Long span shelving is great for storing small to medium-sized items that are hand-picked to order. This type of shelving is much less costly than pallet racking and represents a cost-effective way to bolster your storage capacity.
It can be used to store a wide range of items, including car and other spare parts, hardware, retail items, as well as general carton and archive storage.
Long span shelving is easy to assemble and can be connected together to form rows of shelving in order to optimize the use of floor space. It is easy to assemble without bolts and tools and is powder coated for durability, so it requires minimal maintenance.
Whether it is a single longspan shelving unit for a garage or multiple bays for a warehouse fitout, Falcon Shelving carries a wide range of long span shelving. You can see the range here or contact our expert team for advice or a quote.
3.2 Rivet Shelving
Rivet shelving looks similar in overall shape to long span shelving. It is essentially a cheaper, lighter duty option.
Although rivet shelving uses a different method of attachment, it slots together and can be assembled without tools. This type of shelving often comes flat packed for easy shipping.
3.3 Wire Shelving
Wire shelving is a versatile, light-weight shelving that is known for its durability, ease of assembly and minimal need for maintenance.
It is hygienic. The wire mesh shelves allow excellent airflow around the products being stored, which helps with temperature regulation and preventing the accumulation of dust and debris.
Wire shelving is commonly used to store perishable and temperature sensitive items. This makes it ideal for use in the food & beverage, pharmaceutical, and healthcare industries. Also its moisture resistant nature makes it suitable for use in cold stores.
The shelving can be made from several different materials, which give it different storage properties (see table below).
||Properties and Uses
- Durable and corrosion resistant
- Used in wet humid environments e.g. cool-rooms
- Looks good and very durable
- Used in healthcare, food service, and retail settings as well as cold room storage
- Hygienic and corrosion-resistant
- Used in food processing, pharmaceutical, and clean-room environments
3.4 Mobile Shelving
Mobile shelving, also known as compact shelving, is mounted on wheels or rails. This allows rows of shelving to be compacted together when not in use or moved apart sideways to create an access aisle. Brakes can be fitted to the casters, so that shelves remain stationery when needed.
Eliminating the need for fixed aisles maximizes the available storage space. Mobile shelving is a great option when space is limited and allocating a dedicated space for the required shelving and access is not practical.
Movement of the shelves can be augmented with a hand winding mechanism or with an electric motor to make relocation of the shelves easy.
Mobile shelving is ideal for high density storage applications such as those in healthcare and legal offices.
3.5 Steel Shelving (aka R.E.T or RUT Shelving)
Steel shelving is constructed like a bookcase with a solid steel back and sides and shelves that can be adjusted up and down. This provides open access from the front, and makes it suitable for the hand picking of small, light to medium duty items. It can be set up as a single bay or installed side by side in a long row.
This type of shelving is ideal for general storage, where strong reliable shelving is required. It can also be used in offices for file and archive box storage. Adding accessories like dividers and plastic trays makes it ideal for small parts storage in a warehouse.
Steel shelving is very versatile, which makes it easy to integrate into a wide range of environments, including: warehouses, store-rooms, libraries, museums, retail storage and offices.
4. Specialist Types of Warehouse Shelving
4.1 Cantilever Racking
Cantilever racking is specifically designed for the storage of long, bulky and awkwardly shaped items. It consists of a series of vertical columns in a line that have horizontal arms on which the long items can be stored.
There are two basic types of cantilever racking.
Single-Sided Cantilever Shelving – has horizontal arms on the front side only and can be placed against a wall
Double-Sided Cantilever Shelving – has horizontal arms on both the front and back and requires access aisles on both sides
Cantilever racking makes lengthy materials easy to access. This makes it ideal for the storage of items like lengths of timber, tubing, doors, steel, pipes, and furniture
4.2 Bulk Storage Racks
Bulk storage racks are constructed from robust materials to create a very high load bearing capacity. They are designed to accommodate large and very heavy items that don't fit well on traditional shelving. This makes them suitable for car engines and transmissions, machinery, and other oversized items.
4.3 Tyre Racking
Tyre racking is used to store rimless tyres in a vertical position to minimize warping and distortion (see image below). Tyres can be hand-picked by rolling them out when needed.
Falcon Shelving carries a wide range of tyre racking and you can see the range here
4.4 A-Frame Racking
A-Frame racking is designed in the shape of a capital letter A. Long items can be leaned against the slope of the A-Frame and stored vertically. Stored items are easy to access and the system maximizes the use of vertical space. It is great for long hand-picked items like lengths of timber and pipes.
4.5 Mezzanine floors
A mezzanine floor is a raised storage platform that is used to increase the available floor space. This method of increasing storage is very flexible, both the ground and mezzanine floors can be fitted out with shelving customized to the needs of the warehouse. The mezzanine can also be fitted out as a workspace or office space.
Efficient warehouse storage design relies on using a mixture of different shelving types to accommodate the specific items being stored. In order to make informed decisions about the fitout of a warehouse, it is essential to understand the names and characteristics of the various shelving systems available. This understanding is the first step towards making the right choices and optimizing the overall efficiency of your warehouse.