Narrow Aisles = Big Savings

Why your warehouse layout probably sucks

Douglas Adams description of the Vogon spaceships in Hitchhikers Guide to the Galaxy was that they were not so much constructed as they were "congealed". I feel similarly about many of the warehouses I walk into, which seem to have congealed into a state of dysfunction over time as bits of racking and shelving were just plonked on the floor wherever they seemed to fit. The result is usually poor use of space shown by lots of air around the stock, cheap storage solutions ill configured for the stock they hold, poor placement of product in those storage systems and wide aisles to suit the cheapest forklift available. A series of lowest cost sub-optimal decisions that have congealed into low productivity and high cost of storage. Most warehouses are not designed, they evolve without any vision of what the requirements of the company might be in future. Wasted space and low cost equipment only starts to really be noticed when you grow and start storing stock in your aisles instead of in your racks because you have no room to put it away.

Here endeth the rant.

If only someone had told me this before!

Let me give you a simple formula to live by:

$(Materials Handling Equipment + Storage Systems) < $Warehouse Cost

Warehouse space is not cheap anymore ($150-$300 per sqm p.a.). Materials handling equipment (i.e. forklift) and storage systems have come a long way. Modern equipment is not cheap either but it allows you to increase the storage density in your warehouse and free valuable floor area that is worth much more to you than the cost of the equipment.

For example if you have a 2,000 sqm warehouse with a lease cost of $200 per sqm and increase your storage capacity by 50% using the techniques described here you would save $133,333 per year by staying where you are instead of moving to a larger site (not to mention the cost of moving and the disruption to your business). This will more than pay for the cost of new racking and forklift.

So if you have an old warehouse and you are under space pressure it will be worth your while to find out how to fit more into your existing space. As a side benefit, a carefully designed warehouse layout will also improve your overall productivity as every physical move will also become faster and more efficient as you reduce travel distance per pick, replenishment or put-away move.

Narrow your aisles

One of the key actions you can take to improve storage density and free up warehouse space is to Narrow the aisles between your pallet racks. I drew a diagram to show you exactly how much difference aisle width makes in storage density. You could fit up to 144% more stuff in your warehouse!

You can view this design online at SketchUp

Or watch the video https://youtu.be/CKJeLaVY

The storage capacity differences are charted below:

Forklift Types for Narrow Aisles

You will need a different forklift that works in a narrower aisle. There are a lot of options and brands with varying specifications so the choice of forklift is very important. Which one is right for you will depend on your order and item profile and other constraints and requirements. This is a general guide to what equipment is available and the intended purpose of each type.

Articulating Forklift

Articulating forklifts are still a relatively rare sight in Australia but they are starting to gain acceptance as the cost of warehouse space increases. They are a type of counterbalanced forklift wit a pivot behind the mast that allows it to pivot to each side so it can operate in very narrow aisles of as little as1.9m. But they also do all the normal work of a counterbalanced forklift for general warehouse and yard work (truck loading/unloading). So if you can really only justify the cost of one forklift that has to do everything then a this could be it. Most of them have seats and require the operator to climb on and off so they are more suited to moving pallets than order picking, but Aisle-Master have a new low floor stand on model that is more suited for order picking if that is what you need. Aisle-Master is supplied by Adaptalift in Australia https://www.adaptalift.com.au/new-equipment#brand=aisle-master . The other major manufacturer of articulated forklifts is Bendi supplied by Hubtex https://bendi.com.au/ .

Turret Truck

Turret trucks are a special type of forklift with forks that can swing from side to side and store pallets in narrow aisles less than 2m wide. The cabin may carry the operator up with the forks to make it easy to see where you are placing the pallet and also allow for case picking from pallets. In this case the forks will also have an auxilliary lift to adjust the pallet height as more cases are added to the pallet. Some turret trucks only lift the forks up and the operator stays at ground level, so they can only be used for full pallet movements. Turret trucks are usually large and bulky units and not useful for general forklift activity. There are smaller counterbalanced forklifts with turrets but from my experience they are not common. They are still a little bulky for general use and I have never seen one in use. I think the articulating forklift is probably a more suitable option if you need a machine to do double duty.

Order Picker

An order picker is specifically designed to pick cases from height. It can lift a pallet but the forks do not face sideways so it cannot store or retrieve pallets. It overcomes the slowest movement in warehousing - moving a pallet down from the racks, picking cartons off the pallet and then putting the pallet back into place. The order picker allows the operator to travel in 3D, so they can pick from any pallet in the warehouse. They can work in aisles as narrow as 1.3m. Although they are called "Order Pickers" They are equally good at storing stock on high level long span shelving in very narrow aisle racking as shown in my warehouse model above. In fact I think this is a much better solution for small volume case storage than using mixed pallet storage (multiple items per pallet). It's a little more work to put the stock away but much faster to pick, with better selectivity and much higher storage density. It's worth noting here that order pickers require a special type of forklift licence (LO for order picker and LF for other forklifts).

Reach Trucks

Older warehouses often have 4m-4.5m wide aisles designed for old style counterbalanced forklifts. Reach trucks have long been the standard type of warehouse forklift. Reach trucks can work in aisle widths of as little as 2.8m and 3m is common with larger units needing 3.3m aisles for very high or double deep racking. The main limitation with reach trucks is that they have small wheels with solid tyres and are not good on rough or uneven surfaces. If your truck loading yard is sloping or uneven you may need a counterbalanced forklift for yard work. There are some small counterbalanced forklifts which will operate in a 3m wide aisle but they usually do not have very high lift heights (due to the need for mast tilt). If your warehouse is not very high this may be an option.

Small Order Pickers (Work Assist Vehicles)

Small order pickers do not require a forklift licence and can work in any aisle wider than their chassis which is only ~0.8m wide. They are very easy to drive and allow for quick access to three pallets levels high by any pedestrian picker. They are very useful if you have a large SKU (Item) range and it is not possible to have enough pick faces at pedestrian level. This is way faster than pulling down a pallet to pick from and putting it back up again (and sometimes having to rewrap it). They are relatively inexpensive and much safer and more productive than ladders.

Ladders

Don't use them for order picking, they are unsafe. When carrying one or more boxes down or up a ladder you only have two points of contact (one foot & one hand), which is unstable and risks a fall. Ladders in warehouses have a high risk of injury. They are commonly used. Please consider using a small order picker which will be much cheaper than a lost time injury and the resultant W/C claim.

How I Can Help

I design warehouses as part of my work in helping businesses improve their overall warehouse operations with better layout, process and technology. If you'd like help to optimse your warehouse operations you can message me on Linked in or contact me via my website https://logisticscloudco.com/contact-us/

Watch a video of this Newsletter

If you skimmed over this and would rather watch a video then here it is on YouTube. Whilst you are there please subscribe and see if any of my other videos are of interest.

https://youtu.be/9FA6x_CvZ2Y