Investing in one or more vertical lift modules is one of the best ways for warehouse operators to make more of the space available to them. Composed of vertical columns of trays, with height sensors to place them efficiently and an internal extractor to find, retrieve, and deliver them to an access opening near the base, these systems can provide remarkable floor space savings.
They can also assist with storage density, picking efficiency, and inventory control. However, the benefits you experience from a vertical lift module (or, VLM) are entirely dependent on how you use it. Or, to be more precise, what products you store inside it.
Many users make the mistake of treating their VLMs as a replacement for traditional static shelving units and fail to spend much time considering the SKU profile of the items they place in VLM trays. While it’s easy to think of a VLM as merely a fancy version of a storage rack, in reality, it’s a dynamic and strategic storage solution that demands dynamic optimization.
In this blog, the BoxLogix Automation experts will help you understand which products belong in a vertical lift module and which are better stored in totes and bins elsewhere. We’ll also look at some of the key operational considerations to think about before slotting inventory into a VLM and cover some best practices to enjoy long-term benefits from the module(s) at your disposal.
Many warehouse operators don’t understand the correlation between the contents of a vertical lift module and its overall performance. They assume that the only thing that matters is buying a good quality module, and the benefits will simply manifest themselves from there.
However, if you master the art of placing the correct products into your VLM, in the correct places, that’s when the biggest and best benefits start to appear. A properly optimized module improves picking efficiency, throughput, operator productivity, replenishment efficiency, employee morale, and overall ROI.
Placing fast-moving or high-velocity SKUs in your VLM, for example, can massively improve retrieval speeds and average order preparation times. Putting high-value or delicate items in a VLM, meanwhile, can provide security benefits and combat shrinkage.
On the other hand, if you place items in your VLM almost at random or without sufficient forethought, you’ll still likely see some benefits, but not necessarily enough to make a significant impact on your operations or justify the purchase of the module to begin with.
In short, the trick isn’t to store as much inventory in your vertical lift module as you can. Rather, it’s to store the right types of inventory.
Now let’s take a look at which sorts of inventory should go into a vertical lift module. Note that there isn’t a single “one size fits all” answer here, as every warehouse is different. However, certain groups or sorts of inventory tend to work particularly well in VLMs.
These include:
Arguably the main category of items to almost always include in a VLM is frequently picked or high-demand SKUs. These are the products that pickers spend the most time working with, so you want to make them as easy to access as possible.
Vertical lift modules can vary in size and scale, but often contain relatively compact trays that are best-suited for storing smaller goods. Look for items that fit neatly into trays, aren’t big enough to be stored on pallets, and benefit from being grouped in bulk in dense, vertical storage units.
High-SKU inventory essentially means a broad catalog of products. While some warehouses handle relatively small ranges of goods, others may have huge numbers of unique items, like replacement parts, machine components, and medical supplies. These are ideal for VLMs, since modules can sort and store numerous different items on a relatively small amount of floor space.
Since a vertical lift module is a secure, enclosed space, it’s also well-suited to storing high-value or sensitive items that are at higher risk of being stolen. The VLM helps to control user access to these items, minimizing shrinkage and improving both inventory accuracy and traceability.
G2P systems involve products being delivered directly to operators, reducing walking times and improving labor optimization. Examples of this include fast-moving consumer goods, pharmaceuticals, and spare parts, all of which work well in vertical lift modules.
Just as not all inventory is a perfect match for pick-to-light systems or carousels, not every product belongs in a vertical lift module, either.
In general, larger and bulkier items, such as oversized or extremely heavy items, don’t tend to do well in vertical lift modules, since many have strict weight and capacity limits. A VLM containing large amounts of slow-moving bulk inventory won’t offer much value, either, and products that are typically stored in pallets also don’t generally belong in a VLM.
For the above-mentioned products, it’s usually better to opt for traditional racking or other non-automated storage solutions.
Many operators focus purely on part dimensions and weight when trying to decide if a product should go into a VLM. However, instead of merely focusing on “Will it fit?”, there are several other questions and considerations you should have in mind:
Velocity matters a great deal when it comes to optimizing VLM storage. Products that move fast due to high demand are perfect for these modules, since they can be delivered very quickly to pickers and improve order prep and fulfillment times.
Ideally, you want to strike a balance between making product retrieval more efficient while also easing the burden related to replenishment. Look for products that are in reasonable demand and also replenished regularly to place in your VLM.
If products are commonly picked together, slotting them together can streamline order fulfillment and facilitate faster kitting (grouping of similar items into single packages). It can also reduce operator wait times, improving both throughput and productivity.
Each decision you make related to your inventory should be in the best interests of your broader warehouse operations. Instead of just maximizing storage density or space utilization, this is about making the whole facility more efficient.
Helpful tips to make the most of your VLMs include:
As well as choosing the right products, try to avoid these common errors to get more value from your VLMs:
As previously stated, VLMs aren’t for everything. Choose a collection of SKUs to store in your vertical lift modules, but don’t overlook or underestimate the importance of other storage media.
All major storage decisions in your warehouse should be backed by data. Look at picking history (via your inventory management software or other relevant apps) to find the most in-demand goods.
This can lead to wasted time and energy being expended on needless tray movements, reducing picking efficiency. To avoid it, keep items that are often ordered together close to one another.
Warehouses are always evolving. Operations change, demand ebbs and flows, and inventory may expand or diversify over time. Make sure your slotting strategy evolves alongside your operations.
Setting up a VLM and choosing what to put inside it is only step one of an ongoing process. To truly extract the most value from your module, you have to be able to continuously refine inventory placement as various factors (like order profiles, SKU mix, and customer demand) change.
That’s where BoxLogix comes in. Beyond just helping customers find the right automated storage and retrieval systems, we help them optimize their slotting and refine their placement for long-term operational excellence. Contact our team to learn more.
Vertical lift modules are generally best suited for frequently picked items, small- to medium-sized parts, high-SKU inventory, high-value products, and inventory that benefits from goods-to-person picking. While every warehouse is different, the goal is to store products that will maximize retrieval efficiency, improve space utilization, and streamline day-to-day operations.
VLMs improve warehouse efficiency by making better use of vertical space while reducing the time employees spend walking to retrieve inventory. They can increase picking productivity, improve inventory accuracy, reduce floor space requirements, support faster order fulfillment, and help create a safer, more organized work environment.
The best slotting decisions are driven by data rather than assumptions. Historical picking data, SKU velocity, order history, replenishment frequency, inventory dimensions, and products that are commonly ordered together can all help determine which items belong in a VLM and where they should be stored for maximum efficiency.
Some of the most common mistakes include trying to store every SKU in a VLM, ignoring historical picking data, separating products that are frequently ordered together, and treating slotting as a one-time project. To maximize long-term performance, inventory placement should be reviewed and refined regularly as customer demand, SKU mix, and warehouse operations evolve.
Yes. In fact, small warehouses often stand to benefit the most from vertical lift modules because floor space is typically at a premium. By utilizing otherwise unused vertical space, VLMs can significantly increase storage capacity while improving picking efficiency and inventory organization without requiring a larger facility.
A company should consider investing in a VLM when it is running out of floor space, experiencing slow picking times, struggling with inventory organization, or looking to improve labor productivity and storage density. VLMs can also be an excellent investment for businesses managing large numbers of SKUs or preparing to scale their warehouse operations without expanding their physical footprint.