Pallet racking is the backbone of most warehouses — but a system that's wrong for your pallets, your floor or your forklift is expensive to put right. This guide explains how pallet racking systems are built, the main types, how to size and specify a system, and how to read the load ratings that keep it safe and legal. It's written for buyers specifying racking for the first time or expanding an existing run.
What pallet racking is — the key components
A pallet racking system is a set of standard steel parts that bolt and clip together into adjustable storage bays. Understanding the components makes specifying far easier:
- Upright frames — the vertical towers, made from two perforated uprights braced together. Frame height sets your maximum storage height; frame depth is matched to your pallet depth.
- Beams — horizontal load bars that hook into the upright slots in pairs to form a level. Beam length sets how many pallets sit side by side in a bay.
- Bay — one set of beams between two frames. A "run" is several bays sharing frames end to end, which saves steel and cost.
- Baseplates and floor fixings — every upright sits on a baseplate that is bolted to the floor.
- Beam connector locks / safety clips — pins or clips that stop a beam being knocked out of its slot by a fork truck.
- Decking and accessories — timber or steel deck panels, mesh decks, pallet support bars, and column/end protection.
Our conventional system is a modular, fully adjustable STOW range — beam levels reposition on the upright slots as your stock changes, so the racking adapts rather than being replaced. Browse the full racking and shelving range or the dedicated pallet racking collection.
Types of pallet racking
Most UK warehouses run selective (adjustable) pallet racking — a single pallet deep on each side of an aisle, giving direct access to every pallet. It's the most flexible and lowest-cost-per-bay option and suits the widest range of operations. Other configurations trade access for density:
- Double-deep — two pallets deep, reached with a reach truck and deeper forks; fewer aisles, more storage, slightly slower access.
- Drive-in — the truck drives into a block of rails to deposit pallets; very high density, last-in-first-out, best for large quantities of the same SKU.
- Pallet live / push-back — inclined roller lanes feed pallets forward (FIFO) or back (LIFO) automatically; high density with good rotation.
- Narrow aisle (VNA) — selective racking with very narrow aisles served by a specialist truck; maximises pallet positions in a fixed footprint.
If your loads are long rather than palletised — timber, pipe, board, sheet — cantilever racking is the right tool; see our guide to cantilever vs pallet racking. For hand-loaded boxes and totes, longspan shelving usually beats racking — we cover that in industrial shelving vs pallet racking.
How to size and specify your racking
Good specification starts with your pallets and your truck, not the racking. Work through these in order:
- Pallet size and weight — measure your worst-case pallet (footprint, height including the load, and the heaviest weight). UK standard is 1,200 × 1,000mm, but Euro pallets (1,200 × 800mm) and oversize loads change the frame depth and beam length you need.
- Beam length — choose a beam that takes your pallets side by side with clearance between them and to the frames (typically around 75–100mm each side). Two or three pallets per beam pair is normal.
- Beam levels and pitch — set the vertical gap between levels to your pallet height plus clearance for the forks to lift clear (commonly ~100–150mm). More levels mean more positions but a taller frame.
- Frame height — limited by your truck's lift height, your ceiling/sprinkler clearance and the load. Don't specify height you can't safely reach.
- Aisle width — driven by your truck's turning circle. Counterbalance trucks need wide aisles; reach and VNA trucks need far less. Confirm with your truck supplier before fixing the layout.
- The floor — racking is only as good as the slab it's bolted to. Check the floor is level, sound and thick enough for the point loads under each upright.
Understanding load ratings
Load ratings are where most specification mistakes happen. Three figures matter:
- Beam UDL (uniformly distributed load) — the safe load for a pair of beams, assuming the weight is spread evenly. A single point load or two pallets concentrated in the middle is not the same as a UDL.
- Bay load — the total a bay can carry across all its beam levels.
- Frame/upright capacity — how much a single upright frame can support overall; this depends on the beam pitch (how far apart the levels are), so changing your layout changes the safe capacity.
Because capacity depends on configuration, every installed system should carry a load notice (rack safety sign) stating the maximum beam and bay loads for that specific layout — a requirement under the SEMA code of practice. Never raise beam levels or change the configuration without confirming the new ratings with the supplier.
Safety, inspection and the law
Pallet racking is work equipment, so it falls under the Provision and Use of Work Equipment Regulations 1998 (PUWER) and the Health and Safety at Work Act 1974. The HSE's guidance HSG76 Warehousing and storage and the SEMA codes set the practical standards. In short:
- Racking must be installed plumb, on a suitable floor, and bolted down.
- It must display its load ratings.
- It should be inspected regularly by a trained person, with an "expert" inspection (for example by a SEMA Approved Rack Inspector) at least annually, and damage recorded and acted on using a red/amber/green risk system.
- Impact protection — upright protectors and end-of-aisle barriers — greatly reduces collision damage in trafficked areas.
For the full picture on protecting and inspecting a system, read pallet racking protection: upright guards, barriers and rack safety.
New vs used pallet racking
Used racking can look like a bargain, but mixing brands or components is risky: beams and uprights from different systems aren't always compatible, second-hand steel may carry unseen impact damage, and you rarely get the original load ratings. If you do buy used, buy a known single brand, inspect every component, and have the loadings verified. For most buyers, new racking with documented ratings and matched components is the safer and often more cost-effective long-term choice.
Frequently asked questions
What are the main types of pallet racking systems? Selective (adjustable) is the standard single-deep system. Density-focused alternatives include double-deep, drive-in, push-back, pallet live and narrow aisle — each trades direct access for more pallet positions.
How much weight can pallet racking hold? It depends entirely on the configuration. Beam pairs are rated for a uniformly distributed load and the frame for a total load at a given beam pitch. Always work to the figures on the system's load notice, never a generic number.
Does pallet racking need to be bolted to the floor? Yes. Uprights are bolted down through their baseplates, and the floor must be suitable for the point loads. This is part of safe installation under PUWER and the SEMA codes.
How often should pallet racking be inspected? Trained staff should carry out regular visual checks, with an expert inspection at least once a year (HSG76 / SEMA guidance). Damage should be logged and dealt with promptly.
Ready to specify a system? Browse pallet racking and the wider racking and shelving range, and tell us your pallet sizes, weights, truck type and ceiling height — we'll help you get the bays, beams and load ratings right first time.
This guide is general information, not a substitute for a site-specific racking design or a competent rack inspection. Always follow HSE guidance (HSG76), the SEMA codes and your supplier's load ratings.