“How many stillages do I need?” is one of the most common questions we’re asked at Lowe Stillages & Cages, and it’s a sensible one to work through before you buy. Order too few and you get bottlenecks, double-handling and stock left on the floor; order too many and you tie up capital and warehouse space in units that sit idle. The right number isn’t a guess — it comes from a straightforward calculation based on how much you store, how long each stillage is in use, and how much spare capacity your operation realistically needs.
As a UK manufacturer of steel stillages, cages and post pallets, we help businesses size their fleets every week. This guide sets out a practical, no-nonsense method you can apply to your own site.
Start with what a stillage actually holds
Before you can count units, you need to know how much each one carries. A stillage’s useful capacity is set by two limits — whichever you hit first governs how much you can load:
- Volume (cube): the internal dimensions determine how many items, boxes or components physically fit inside. For bulky, lightweight goods you’ll usually run out of space before you run out of weight.
- Safe working load (SWL): every stillage has a rated capacity for static storage and, where applicable, a separate rated limit for stacking and lifting. For dense goods — castings, fixings, wet materials — weight is the binding constraint, not cube.
Work out your realistic fill per stillage, not the theoretical maximum. Irregular shapes, packaging and safe stacking heights all reduce usable capacity. If you’re unsure which dimensions and load ratings suit your product, our buyer’s and design guide walks through it in detail.
A simple method to calculate the number you need
Once you know what one stillage holds, sizing the fleet follows a repeatable sequence. Use consistent units throughout (per day or per week).
1. Establish your peak stock volume
Look at how much stock you actually need to hold at once — not your average, but your realistic peak. Seasonal ranges, promotional runs and safety stock all push the peak above the everyday figure. Divide that peak volume by the usable capacity of one stillage to get your base storage requirement.
2. Add the units in circulation
Storage is only part of the picture. In most operations, stillages are also moving — being filled at the line, in transit, out with a customer or supplier, waiting to be emptied, or being cleaned. Count how many are typically “in flight” at any one time. The longer the cycle from filling a stillage to getting it back empty, the more units you need to keep the process flowing.
3. Factor in turnover and cycle time
Turnover is the multiplier most people underestimate. If a stillage completes one full cycle a week, you need far more of them than if it turns around in a day. As a rule of thumb, the number tied up in circulation is roughly your throughput rate multiplied by the average cycle time. Faster, more disciplined handling reduces the fleet you need to own.
4. Build in a spares buffer
Never size a fleet to run at 100% utilisation. You need spare units to absorb demand spikes, cover stillages that are out for repair or inspection, and keep the operation moving when returns are delayed. A buffer of around 10–20% on top of your calculated total is a sensible starting point — tighten or loosen it based on how predictable your demand is.
Put simply:
- Base storage need (peak stock ÷ usable capacity per stillage)
- + units in circulation (throughput × cycle time)
- + spares buffer (typically 10–20%)
- = your recommended fleet size
Match the right stillage type before you multiply
Getting the count right depends on getting the type right first. Ordering a large quantity of the wrong specification is an expensive mistake to unwind. Consider:
- Stacking vs. non-stacking: stackable units multiply your effective floor capacity, which can reduce the number you need for a given footprint.
- Fixed vs. collapsible: collapsible pallets and stillages fold down when empty, cutting return-transport and storage costs — valuable if units spend time off-site.
- Standard vs. bespoke: a design tailored to your product can raise usable capacity per unit and improve handling, which changes the maths in your favour.
Review your space and current fleet
Your building sets hard limits, so plan the count against the space you have. Map out where stillages will live — racked, block-stacked or in dedicated zones — and confirm your stacking heights against the units’ rated limits and your safe handling policy. Our guide on keeping stillages stable and safe covers stacking and storage without risking collapse.
If you already run a fleet, audit it before adding to it. Identify units that are idle, damaged or the wrong size for current work — freeing up or replacing these can reduce how many new ones you actually need. For sites with unusual products or tight space, a bespoke stillage solution often makes better use of both the units and the room they occupy.
Don’t forget safety and compliance in the count
Fleet sizing isn’t only a numbers exercise — the equipment has to be safe and legal to use. In the UK, work equipment is governed by the Provision and Use of Work Equipment Regulations 1998 (PUWER), and any stillage used in lifting operations also falls under the Lifting Operations and Lifting Equipment Regulations 1998 (LOLER). Lifting stillages require periodic thorough examination, so build in enough spare units to keep operating while others are out for inspection.
Our stillages are UKCA marked where certification applies, and you can read more on safe use in our workplace stillage safety guide.
A worked example
Imagine a workshop that ships components in stillages holding 300kg of usable stock each:
- Peak stock on hand needs 20 stillages just for storage.
- On any given day, around 8 units are in circulation — being filled, in transit, or out with customers on a weekly return cycle.
- That gives a working total of 28 units.
- Adding a 15% buffer for spikes, repairs and inspections brings the recommendation to roughly 32 stillages.
The figures will differ for every operation, but the method is the same: capacity per unit, plus units in motion, plus a sensible buffer.
Get an accurate figure for your operation
The most reliable way to land on the right number is to share your real requirements — product type, weights, dimensions, throughput and available space — and let us do the sizing with you. Our guide on giving us the right technical information shows exactly what to gather so your quote reflects what you actually need.
Ready to size and specify your fleet? Request a free quote or contact the Lowe team for tailored guidance — we’ll help you order exactly the right number, in the right specification, first time.