Vertical Carousels & VLM Storage Systems: A Buyer's Guide

If your operation is running out of floor space, the instinct is to build out or lease more square footage. Automated vertical storage offers a different answer: go up instead of out, and bring the inventory to the worker rather than sending the worker to the inventory. This guide explains how the three main systems — pan carousels, shelf carousels, and vertical lift modules (VLMs) — actually work, how much space each reclaims, and how to match one to your ceiling height, SKU profile, and pick volume. Reynolds reads this from the implementer's seat: we carry the Hänel and Vidir lines named here and have been an authorized vertical-storage dealer since 1990.

How vertical carousels and VLMs work

All of these systems share one principle — goods-to-person — but they reach it two different ways. A vertical carousel uses motorized carriers attached to a chain drive that rotate vertically in a looped track, like a Ferris wheel: every carrier moves together until the requested one arrives at an ergonomic access point. A vertical lift module is a stationary tower with an inserter/extractor that retrieves an individual tray and brings it to an access opening at ergonomic height — only the one tray you need moves, not the whole loop.

That mechanical difference drives the selection logic. Reynolds explains it the same way: pan and shelf carousels rotate all carriers together like a Ferris wheel, while a VLM is a stationary tower with a tray extractor that retrieves individual trays.

How much floor space you actually reclaim

The space case is the headline reason most operations look at these systems, and the documented numbers are substantial. The exact figure depends on your ceiling height, tray pitch, and SKU profile, but the manufacturer ranges are consistent:

Reynolds frames its own line the same way: pan carousels deliver roughly 75% floor-space savings, shelf carousels about 70%, VLMs up to 85%, and specialty carousels 60-80% — generally 70-85% versus conventional shelving. A concrete illustration makes the density gain tangible: about 50 sq ft of floor space can store the equivalent of 300+ sq ft of conventional shelving. Kardex puts it in shelving terms — a single VLM can store the same inventory as 120 bays of static shelving.

Picking speed, accuracy, and labor

Beyond the footprint, the operational case is throughput. Because the item travels to the worker instead of the worker walking, climbing, and searching, picking gets faster and more accurate. Kardex reports that goods-to-person automated storage improves pick efficiency by 200-300%, and that pick-to-light guidance can reduce picking errors by up to 99%. Kardex Shuttle VLM customers report 99.9% pick accuracy, 85% floor-space savings, and a 67% reduction in labor force. Reynolds' page cites up to 400% faster picks (4x) and 99.9% accuracy for automated vertical storage.

The ergonomics and safety case

For labor-constrained or regulated facilities, the injury-reduction case is often as compelling as the space case. Automated vertical storage delivers items to the OSHA-defined 'Golden Zone' — the area nearest the core of the body between the shoulders and knees — minimizing the bending, reaching, and climbing that drive musculoskeletal injuries.

Hänel documents the stakes: overexertion from handling objects accounts for over $13 billion in annual workplace injury costs, the average musculoskeletal-disorder compensation claim exceeds $32,000, and ergonomic improvements can reduce missed work days by as much as 77%.

ROI and payback

The common industry benchmark Kardex cites for VLM ROI is about 18 months — and in a Kardex customer survey, nearly 80% reported achieving ROI in under a year. Reynolds positions a typical window of 12-24 months and a 10+ year system lifespan for these systems. Payback comes from three levers working together: reclaimed floor space (avoiding a build-out or lease), labor reduction, and fewer errors and injuries. Because every number depends on your wage rates, square-footage cost, and throughput, the honest move is to model it against your facility rather than assume a single figure.

Specialty applications

Standard pan and shelf carousels are optimized for uniform small-to-medium parts — fasteners, electronic components, maintenance supplies. When inventory is heavy, long, or oddly shaped, a purpose-built carrier beats forcing it into a standard tray system. Reynolds offers specialty-application carousels for non-standard loads — tire, wire spool, bar stock, and rolled goods — and Vidir publishes dedicated tire and textile carousel lines that recover up to 70% of floor space.

How Reynolds approaches it

Reynolds is a 55-year Lehigh Valley implementer — not a manufacturer — which means the recommendation isn't tied to one product line. We have been an authorized vertical-storage dealer since 1990, with 3,000+ systems installed and 100% client retention, and we carry the lines named throughout this guide: Hänel (named on our page as the VLM and carousel inventor — Rotomat, LeanLift, Effimat) and Vidir vertical-storage systems. Because we specify, install, and service locally, you work with the same team from assessment through service rather than routing through a national chain.

Choosing between a pan carousel, a shelf carousel, and a VLM comes down to your ceiling height, SKU profile, and pick volume — the variables a brochure can't know. That's where a site assessment turns published ranges into a configuration sized for your facility.

Where to go next

Ready to size a system for your facility? See Reynolds' vertical carousels & VLMs for the full Hänel and Vidir line and to request a facility assessment, or explore

specialty carousels for tires, wire spools & rolled goods if your inventory is heavy, long, or oddly shaped — and review our broader

automated storage systems and

high-density storage solutions for the full picture, all within our

storage solutions overview.