Most operators sign a greenfield warehouse lease, then call us to quote racking. By then, the column grid is fixed, the slab spec is poured, and the forklift fleet is already on order. We spend the first site meeting explaining why the 3.6 m aisle they assumed won't work with their chosen reach truck, or why the 15 kN/m² slab they negotiated can't safely carry the 2,500 kg pallet load they're planning to stack four-high.

The smarter operators bring us in earlier — sometimes before the lease is even signed. Not because we design buildings (we don't), but because the racking layout determines whether the building actually works. In this article, we walk through the decisions you can lock down before tenancy, the ones that save you from discovering six months in that you've leased the wrong shell.

Why Greenfield Warehouses Fail at the Racking Stage

A greenfield warehouse is a blank shell — no existing racks, no legacy column obstructions, no inherited layout mistakes. That sounds like freedom, but it also means every decision is yours to get right or wrong.

We've been called to three greenfield sites in the past 18 months where the operator signed a 10-year lease, then discovered:

• The building's 10 m clear height looked generous on paper, but after deducting sprinkler drop, lighting, and beam depth, the usable pallet height maxed out at 7.2 m — one level short of what the business case assumed.
• The developer's standard 3.5 m aisle width worked for counterbalance forklifts, but the operator had already bought VNA trucks that needed 1.8 m aisles and guide rails — which the slab wasn't designed to anchor.
• The slab was poured to 12 kN/m² because "that's what logistics buildings get," but the SKU mix (bulk oils in 1,000 L IBCs) generated a 3,200 kg pallet load that needed 18 kN/m² minimum once stacked.

None of these are unfixable, but all of them cost money and storage density that didn't need to be lost. The fixes — slab reinforcement, shorter racks, wider aisles — turn a greenfield advantage into a compromise you'll live with for a decade.

The Racking Decisions You Can Lock Down Before Lease Signing

You don't need final SKU counts or a finished WMS to make the structural calls. You just need to know enough about your operation to specify the building correctly. Here's what we help clients confirm before they commit.

1. Forklift Fleet and Aisle Width

This is the single biggest determinant of your floor plan. A counterbalance forklift needs 3.3–3.6 m aisles. A reach truck needs 2.6–2.8 m. A VNA truck needs 1.6–1.8 m, plus guide rails and sometimes wire guidance.

If you don't specify aisle width in the lease, the developer will pour a column grid that "looks about right" — usually 24 m bay spans with 3.5 m aisles, because that's the safe middle ground. If you later realise you want VNA for density, you're stuck with aisles that waste 1.8 m per run, or you accept lower pallet positions than the building could have supported.

We ask clients: what's your forklift strategy? If you don't know yet, we model two or three scenarios (counterbalance, reach, VNA) with realistic aisle widths and show the pallet position difference. That number — say, 1,200 pallets vs. 1,800 — often clarifies the forklift decision faster than any fleet consultant.

2. Pallet Load Case and Slab Capacity

The developer's structural engineer will pour a slab to a loading spec, typically 10–15 kN/m² for general logistics. That's fine for light cartons and mixed goods, but not for liquids, tiles, machinery spares, or any SKU where a single pallet exceeds 1,200 kg.

We calculate the actual floor load based on your pallet weight, rack beam spacing, and the number of pallets per bay. A 2,000 kg pallet stacked four-high in a 2.7 m bay with 0.9 m beam spacing generates approximately 16 kN/m² at the base. If the slab is only rated to 12 kN/m², you either reduce stack height (losing capacity), space the racks further apart (losing density), or reinforce the slab after the fact (expensive).

The fix is simple if done early: tell the developer's engineer your expected pallet load and stack height, and have them pour to 18 or 20 kN/m². The cost difference at the concrete stage is marginal. The cost difference after tenancy is not.

3. Clear Height and Usable Racking Height

A 10 m clear height doesn't mean 10 m of racking. You lose height to:

• Sprinkler system drop (typically 300–500 mm depending on pipe diameter and in-rack vs. ceiling-only coverage)
• Lighting, cable trays, HVAC ducts (another 200–400 mm)
• Top beam clearance for forklift mast and load (minimum 100 mm, often 150 mm for safety)

That 10 m shell realistically gives you 8.8–9.0 m of usable height. If your business case assumed five beam levels at 2.0 m intervals (needing 10 m), you're now stuck at four levels, or you squeeze the vertical spacing and create headroom issues for your forklifts.

We recommend clients ask for the building's internal clear height measurement after all services are installed, not the structural slab-to-slab dimension. If the developer hasn't finalised services yet, we assume a 1.0–1.2 m deduction and plan racking to that.

4. Column Grid and Bay Layout

The building's column spacing determines your rack bay width. A 24 m column span can fit three runs of 7.2 m racks (with two 3.6 m aisles), or four runs of 5.4 m racks (with three 2.7 m aisles), or five runs of 4.2 m racks (with four 1.8 m aisles for VNA).

If the developer pours columns at 20 m spans because it saves steel, you lose flexibility. You can't fit clean multiples, so you end up with one short run, or wasted floor space at the edges, or racks that don't align with the building grid and create awkward turning zones.

We've worked on greenfield sites where the operator negotiated column spacing as part of the lease terms. It's not common, but it's also not impossible — especially if you're the anchor tenant or signing a long lease. The developer's structural engineer can usually accommodate a 22 m, 24 m, or 26 m span without major cost impact, as long as you ask before the steel is ordered.

5. Mezzanine and Overhead Clearance

If your operation includes a mezzanine — for pick faces, packing stations, or office overlay — you need to confirm the clear height supports it. A mezzanine floor typically requires 2.4 m clearance below (for personnel + lighting + services) and 2.2–2.4 m above (same reason). That's 4.6–4.8 m minimum, plus the mezzanine structure itself (200 mm steel deck + beams).

If your building is only 8 m clear and you add a mezzanine, you're left with 3.2 m below and 3.8 m above after structure — tight for racking, and uncomfortable for people. We've seen operators squeeze it in, then realise the mezzanine can't accommodate pallet racking underneath because there's no forklift headroom.

If you know you want a mezzanine, either negotiate a taller building (10–12 m clear), or plan the mezzanine area as a separate zone with lower racking adjacencies.

What You Don't Need to Decide Yet (But Should Be Thinking About)

Some decisions can wait until after you've taken tenancy, but they should still inform your building spec. These include:

• Exact beam level heights: You can adjust these once you know your SKU mix, but the building's clear height sets the upper limit.
• Rack depth (single-deep, double-deep, drive-in): This affects aisle count and density, but you can model it once you know your SKU velocity and FIFO requirements.
• Seismic bracing and upright protection: These are installation details, but they don't change the building spec.
• BCA mezzanine submission: If your mezzanine exceeds 100 m² or supports heavy machinery, it will need a PE-stamped submission. We coordinate this, but it happens after lease signing.

The key is to preserve optionality. If you spec the building correctly — slab load, clear height, column grid, aisle width — you can refine the racking layout later without structural regret.

How We Help Clients Plan Greenfield Racking Before Tenancy

When a client brings us in at the pre-lease stage, we don't design the building — that's the developer's architect and engineer. But we do provide the operational inputs they need to spec the building for racking.

Our typical pre-tenancy scope includes:

• A forklift-to-aisle-width study, showing pallet capacity under two or three equipment scenarios
• A pallet load calculation and recommended slab capacity, based on your expected SKU weight range
• A preliminary bay layout aligned to the proposed column grid, so you can see whether the building actually fits your operation
• A clear-height deduction estimate, so you know how many beam levels you can realistically install
• A mezzanine feasibility check, if you're planning overhead floors or offices

This isn't a full racking quote — you don't have a final SKU list or WMS config yet — but it's enough to inform the building spec. We've done this for 3PL operators taking anchor tenancy in new logistics parks, manufacturers building custom production warehouses, and cold-chain operators leasing temperature-controlled shells.

The cost of this early-stage work is minimal (usually a few hundred dollars, credited back if you proceed with the racking install). The cost of not doing it — discovering after tenancy that your building doesn't fit your racking needs — is orders of magnitude higher.

The One Thing Every Greenfield Operator Should Do Before Signing

If you take nothing else from this article, do this: before you sign a greenfield lease, ask the developer's engineer for the slab load rating, the internal clear height after services, and the column grid dimensions. Then send those specs to us (or any competent racking contractor) and ask: "Can I fit X pallets in this building with Y forklift type?"

If the answer is no, or if the numbers are tight, you have leverage to negotiate. Maybe the developer can pour a stronger slab, or increase the clear height by 500 mm, or adjust the column spacing by 2 m. These changes are cheap at the design stage and impossible after construction.

If the answer is yes, you've de-risked the single biggest operational assumption in your lease. You know the building will hold the racking you need, at the density you planned, with the forklift fleet you're buying. Everything else — the exact beam heights, the upright frame spec, the seismic bracing — we can sort out once you've moved in.

Frequently Asked Questions

Can I design the racking layout before the building is even built?

Yes, and in fact it's easier than designing around an existing building. We work from the proposed floor plan and column grid (usually provided by the developer's architect) and model the racking layout as if the shell were already there. The only unknowns are services — sprinkler drop, lighting, cable trays — so we build in a conservative height deduction (1.0–1.2 m) and refine it once the MEP drawings are final. This approach lets you confirm the building will work before you commit to the lease.

What if I don't know my exact pallet load yet?

You don't need an exact number, but you do need a realistic range. If you're storing electronics, your pallets might be 400–800 kg. If you're storing tiles, liquids, or machinery parts, they might be 1,500–2,500 kg. We calculate the slab load for the upper end of your range and add a safety margin. If your SKU mix changes later and pallets come in lighter, the building is still fine. If they come in heavier and you under-spec'd the slab, you're stuck. It's always safer to over-spec at the concrete stage.

Do I need to decide between selective, double-deep, or drive-in racking before tenancy?

Not necessarily, but you should at least model the aisle width implications. Selective racking (one pallet deep) and double-deep racking use the same aisle widths — 2.6–3.6 m depending on forklift type. Drive-in racking has no aisles between bays, only entry lanes, so it needs wider column spans and changes the floor plan significantly. If you think you might want drive-in, tell us early so we can check whether the building's column grid supports it. If you're definitely going selective or double-deep, the building spec is more forgiving.

How much does it cost to get a pre-tenancy racking feasibility study?

For most greenfield projects, we charge a few hundred dollars for a preliminary layout and load study — basically enough to confirm the building works for your operation. If you proceed with us for the racking fabrication and install, we credit that fee back. If you don't proceed, you've still got a layout you can use to negotiate with the developer or take to another contractor. We'd rather spend a few hours up front and get the building right than spend weeks after tenancy trying to fix a mismatch between your lease and your racking needs.

What happens if the developer won't change the building spec?

Then you adjust your operational assumptions to fit the building, or you walk away and find a shell that does work. We've had clients do both. In one case, the developer's standard 12 kN/m² slab couldn't support the client's pallet load, and the developer refused to upgrade (multi-tenancy building, couldn't customise for one tenant). The client re-negotiated a different unit in the same park that had been spec'd for cold-chain use, which came with a 20 kN/m² slab as standard. In another case, the operator accepted the lower slab rating and reduced stack height from four levels to three — losing 25% capacity, but still making the lease work financially. The key is knowing the constraint before you sign, not after.

Ready to Plan Your Greenfield Warehouse Racking?

If you're evaluating a greenfield warehouse lease in Singapore and want to confirm the building will fit your racking needs before you commit, send us the developer's floor plan and your expected pallet load. We'll model the layout, flag any structural mismatches, and give you the inputs you need to negotiate the building spec while you still have leverage.

Reach us on WhatsApp at +65 9107 2601 — we've been doing this for two decades, and we'd rather spend an hour up front than watch you sign a 10-year lease on a building that doesn't work.