We've built both systems across hundreds of Singapore installs — long-span shelving for electronics distributors stacking cartons, cantilever for timber yards running 6-metre lengths of hardwood. The decision between the two isn't about industry or "what everyone else uses." It comes down to one thing: whether your load sits cleanly on the beam, or whether it overhangs, protrudes, or needs to be pulled laterally without a front upright in the way.

Here's how we walk clients through it, and what we check before we fabricate a single frame.

What Long-Span Shelving Actually Is (And When We Build It)

Long-span shelving is selective racking without the pallet. You've got vertical uprights at the front and back, horizontal beams spanning between them, and usually a chipboard, wire mesh, or steel deck sitting on top of the beams to spread the load.

We fabricate these for:

• Carton storage — electronics, pharmaceuticals, apparel in boxes that don't warrant a full pallet position
• Archive and document storage — file boxes, lever-arch files, rolled plans in tubes
• Light industrial parts bins — automotive components, FMCG overflow, retail backstock
• Multi-level picking environments — integrated with mezzanines where operators walk between aisles and hand-pick SKUs

The key characteristic: the load is supported along its entire footprint, front to back. You're not hanging anything off the edge. You're resting it on a deck or beam pair, and the upright frames at each end take the vertical load through compression.

Typical beam capacities we fabricate for long-span: 300 kg to 1,000 kg per level, depending on beam profile, span length, and whether the deck is continuous or slatted. We've gone higher — 1,500 kg per level for a dense archive install in Woodlands — but at that point you're approaching selective pallet racking load cases, and the economics tilt accordingly.

What Cantilever Racking Actually Is (And When It's Non-Negotiable)

Cantilever has no front upright. The arms project horizontally from a central column (or a back-braced frame), and your load sits on top of those arms — or between them if you're storing vertically.

We build cantilever when:

• The product is longer than any reasonable beam span — steel bar stock, aluminium extrusions, copper pipe, timber planks, PVC conduit, anything running 3 to 12 metres
• You need to pull stock out sideways — no front upright means forklifts (or overhead cranes) can extract loads laterally without obstruction
• The product has irregular cross-section — bundles of rebar, I-beams, rolls of fabric or vinyl that won't sit neatly on a shelf deck
• You're stacking vertically and need adjustability — sheet goods (plywood, MDF, acrylic) stored on-edge between cantilever arms

The critical difference: cantilever arms resist bending loads. Unlike a beam supported at both ends, a cantilever arm is like a diving board — the load creates a moment at the base where it connects to the upright column. The further out the load sits, the higher the bending stress. This is why arm length, arm profile, and base-plate weld quality matter enormously, and why we always ask for the actual load position along the arm, not just the total weight.

Typical arm capacities we work with: 500 kg to 2,000 kg per arm, single-sided or double-sided configuration. We've fabricated heavy-duty cantilever rated to 3,500 kg per arm for a Jurong metalworks client storing 12-metre structural steel sections, but that required imported heavy-section columns and PE-stamped calculations.

The Load Case That Decides Between Them

When a client calls us and says "we need shelving for long products," the first question we ask is: does the product overhang the support point?

If the Load Sits Fully Supported Between Two Beams → Long-Span

A 2.4-metre length of MDF, sitting flat on a 2.7-metre-wide long-span shelf deck, load centred, picked from the front aisle by hand or pallet jack — this is a textbook long-span application. The load is in compression on the deck, the deck transfers it to the beams, the beams transfer it to the uprights. Simple, stable, economical.

If the Load Overhangs, or You Need Lateral Access → Cantilever

A 6-metre steel bar sitting on 1.2-metre cantilever arms — half the length is hanging in mid-air beyond the arm tip. The arms bend under that moment load. If you tried to rest that same 6-metre bar across two beams in a long-span frame, you'd either need a 6-metre beam span (structurally inefficient and expensive), or the bar would overhang dangerously at the ends, creating trip hazards and potential collapse if bumped.

Cantilever solves this by design: the arms are engineered to handle overhang. We calculate the moment based on load weight, load centre of gravity, and arm projection, then size the arm profile and base connection accordingly.

The Forklift Access Question

We've seen clients choose cantilever not because of load overhang, but because their forklift operator needs to approach from the side or at an angle. In a long-span system, front uprights create a grid — you're loading and unloading from the aisle face only. In cantilever, the open front means you can drive in perpendicular and pull a 10-metre piece of timber straight out sideways. If your workflow depends on that, cantilever is non-negotiable.

What We've Seen Go Wrong (And How We Prevent It)

Most of the call-outs we get to "fix" racking involve someone choosing the wrong system based on catalogue photos, not load case analysis.

Long-Span Built Where Cantilever Was Needed

A Pandan warehouse storing 4-metre lengths of extruded aluminium profile across long-span beams spaced at 2.4 metres. The overhang on each end was nearly a metre. First forklift bump, the profiles slid off. They called us to retrofit cantilever arms. Cost them double what it would have cost to spec it correctly upfront.

Cantilever Built Where Long-Span Would Have Worked

A Woodlands distributor storing cartons of automotive filters, each carton 600 mm × 400 mm. They were quoted cantilever because "the sales guy said it's more heavy-duty." The arms were oversized, the floor fixings were over-engineered, and they paid 40% more than a long-span system would have cost for the same cube utilisation. We re-laid it out with long-span and reclaimed two aisles' worth of floor space.

Cantilever Arms Underrated for Actual Load Position

We've inherited two installs where the cantilever was rated for "1,000 kg per arm" but no one asked where that 1,000 kg sits. The client was stacking coils of wire mesh right at the tip of the arm, maximising the bending moment. Arms were visibly sagging within six months. We had to retrofit heavier-profile arms and add mid-span bracing.

This is why we always ask: what's the load, and where on the arm does it sit? A 1,000 kg load centred at 400 mm from the column is not the same load case as 1,000 kg centred at 1,000 mm out.

How We Actually Spec the System

When you engage us for long-span or cantilever, here's what we do before we quote:

• Site survey — measure floor slab thickness, check for underfloor services, confirm ceiling height and any obstructions (sprinklers, cable trays, HVAC ducts)
• Load profile — weight per SKU, dimensions (length × width × height), how it's bundled or stacked, whether it's palletised or loose
• Forklift or handling equipment details — if you're using a sideloader, reach truck, or overhead crane, we need to know mast height, aisle width, and turning radius
• Pick frequency and access pattern — front-only access, or do you need to pull from the side? Full-pallet retrieval, or hand-picking individual pieces?
• Floor loading capacity — especially critical for cantilever, where point loads at the base can exceed 10 kN per upright on a heavy-duty double-sided system

From there, we run the beam or arm calculations, design the layout to maximise your usable height and aisle efficiency, and provide a line-item quote with material specs (beam profile, arm thickness, upright gauge, decking type) and lead time.

When to Combine Both in the Same Warehouse

We've done mixed layouts where one zone is cantilever (for long steel and timber) and another zone is long-span (for cartons and small parts). There's no rule that says you must choose one.

A Tuas industrial supplier we worked with last year runs cantilever along the back wall for 6-metre conduit and cable tray, and long-span racking with mezzanine pick-faces in the centre of the warehouse for electrical fittings and junction boxes. Different load cases, different systems, same building.

If your SKU mix has both long/unwiedy items and carton goods, we'll lay out a hybrid solution and label each zone by system type in the AutoCAD plan so your team knows what goes where.

Frequently Asked Questions

Can I store pallets on long-span shelving?

Technically yes, if the beam and deck are rated for it — but at that point you're better off using selective pallet racking, which is purpose-built for pallet loads and forklift access. Long-span is more economical when you're storing loose cartons, bins, or archive boxes that don't need the full 1,000 kg–2,500 kg capacity of a pallet beam. We'll tell you honestly if selective racking is the better fit.

How much overhang can a cantilever arm handle?

It depends on the arm profile, the load, and where the centre of gravity sits. As a rule of thumb, we design cantilever so that no more than 50% of the product length overhangs the arm tip — but we calculate it properly based on bending moment. If you've got 8-metre steel bar and 1-metre arms, we'll flag that as unsafe and recommend longer arms or a reconfigured layout.

Do I need floor fixings for long-span shelving?

Usually no — long-span is relatively light and stable because it has front and back uprights. We use floor anchors when the system is over 4 metres tall, when the aisle is narrow and there's forklift traffic, or when the warehouse is on a suspended slab with limited lateral restraint. Cantilever, on the other hand, always needs floor fixings because of the unbalanced moment load.

Can cantilever arms be adjusted after installation?

Yes. We fabricate cantilever uprights with bolt-hole spacing at regular intervals (typically every 100 mm vertically) so you can move arms up or down as your product mix changes. It's one of the advantages over welded shelving. You'll need to unload the level, unbolt the arm, reposition, and re-torque — but it's doable without cutting or re-welding.

Which system is more expensive?

Cantilever costs more per linear metre because the engineering is more complex and the steel sections are heavier. A double-sided cantilever bay might run 30–50% more than an equivalent long-span frame. But if cantilever is the right load case, trying to save money with long-span will cost you more in safety risk, product damage, or needing to rip it out and rebuild. We quote both if the load case allows, and we'll tell you which one we'd choose for our own warehouse.

What Happens Next

If you're not sure whether your product suits long-span or cantilever — or if you've been quoted one system and want a second opinion — send us a photo of what you're storing and the dimensions. We'll tell you what we'd build, and why.

You can reach us directly on WhatsApp at +65 9107 2601.

Related: Cantilever racking in Singapore — when you actually need it.

Also worth reading: storing cable drums, coils and rolls — why round loads break the assumptions pallet racking is built on.