Pictured above: selective racking at our V3-3 project, an ambient warehouse. The frame family is the same one that goes into chillers and freezers — what changes is the finish, the floor detail and how the room is worked. That is what this article is about.

The first thing to say about cold room racking is that it is mostly the same racking. The uprights, beams and connectors come from the same families we install in ambient warehouses, and a customer who has already been through a selective racking project will recognise everything.

What changes is the environment it has to survive, the floor it has to stand on, and the fact that people can only work in there for so long at a stretch. Those three things account for the whole difference in price, programme and design — and they catch people out in that order.

Chiller and freezer are not the same problem

Operators tend to say "cold room" for both, but from a racking point of view they behave very differently.

A chiller is a wet environment. It sits above freezing, warm humid air comes in every time a door opens, and moisture condenses on cold steel and stays there. Corrosion is the governing issue, and it attacks cut edges, welds, connector holes and anywhere the finish has been chipped by a pallet.

A freezer is a dry environment once it is at temperature — water is frozen out of the air rather than sitting on surfaces. The governing issues there are different: frost accumulation, what the slab is doing underneath, and the fact that steel and people both behave differently at those temperatures.

Designing a freezer as if it were a cold chiller, or vice versa, is the most common way to get this wrong.

The finish decision, and why it is not optional

Standard powder-coated racking is designed for a dry, ambient warehouse. Put it in a chiller and the finish is doing a job it was not chosen for: constant condensation, wet pallets, and washdown regimes in food environments that involve chemicals as well as water.

The practical options are a more durable protective finish, or galvanised components, and the right answer depends on the room's temperature, the humidity regime, whether it is a food environment and how it is cleaned. The cost difference is real, and it is worth understanding that this is the one specification decision you cannot revisit later — you can change beam levels in an afternoon, but you cannot re-finish an installed frame.

The place this matters most is the bottom metre of every upright, which sits in whatever ends up on the floor. It is also, not coincidentally, where forklift impact happens.

The floor, which is the part nobody expects

This is where cold storage genuinely differs from ordinary racking work, and it is worth insisting on before anything is designed.

Freezer floors are built up: insulation, and in many cases a heating arrangement below the slab to stop the ground beneath freezing and heaving over time. That build-up is not something to drill into on the assumption that it behaves like a normal warehouse slab. Anchoring racking into a cold-store floor without the slab build-up drawing in front of you is a genuine risk — to the floor, to the frost-protection system, and to the warranty on both.

So the first request on any cold storage enquiry is the same one we make for a ramp-up warehouse: the drawings, before the layout. What the slab is, what is in it, and what its permitted loading is. Where fixing is constrained, the design has to work with that — different base arrangements, load spread, or a frame configuration that reduces the number of fixing points — and all of those are design decisions rather than site improvisations.

Floor flatness matters here too, for the same reasons it matters in a VNA conversion: a tall frame amplifies whatever the floor is doing at its base.

Airflow: the racking can stop the room working

A cold room cools by moving air. Evaporators throw air across the space and it has to come back. Fill the room with a solid block of racking and pallets and you can create dead zones where the temperature is several degrees off the rest of the room — a serious problem when the whole point is a documented cold chain.

Practically, this means clearances are not wasted space: gaps behind back-to-back runs, clearance under the bottom beam, and keeping the evaporator throw path clear rather than parking a top-level pallet in front of it. Mesh decking is generally preferable to solid boards for the same reason, with the added benefit that it does not hold water and is easier to keep clean in a food environment.

This is a case where the densest layout is not the best layout, which is a theme that also runs through drive-in density in practice.

Installing in a working cold store

Installation is slower and it costs more, and it is worth knowing why before comparing quotations.

Nobody installs steel at freezer temperature for a full shift. Crews rotate, breaks are frequent and mandatory, tools and hands behave differently, and the productivity per hour is simply lower than the same work in an ambient warehouse. If the room has to stay in operation, the work is staged section by section — and if it can be brought up to temperature, there is a defrost, a dry-out and a pull-down cycle at either end that belongs in the programme rather than being discovered at the end of it.

A quotation that prices cold store installation at ambient rates is not cheaper. It is a quotation that has not thought about the room.

Living with it afterwards

Two things are worth planning for on day one.

The first is inspection. Racking in a cold store still needs routine inspection, and it is harder — frost hides impact damage, the light is usually worse, and nobody wants to linger. That makes a defined inspection routine more important here than in an ambient warehouse, not less. We cover what one should involve in the racking inspection checklist.

The second is the doorway. The first bay inside a cold room door takes disproportionate abuse — restricted visibility through strip curtains, forklifts turning in a tight space, and drivers in a hurry to stop losing cold air. Column guards and end-of-run protection at the entry bays are worth more here than anywhere else in the building. The wider pattern is in forklift impact patterns.

Fire safety, which is its own conversation

Sprinkler arrangements in cold storage are not the same as in an ambient warehouse, and the rack layout interacts with them — clearances, flue spaces and the position of runs relative to the sprinkler design. If your building has an approved arrangement, the racking layout has to respect it, and that is settled with the layout rather than after installation. The general principle is the same one in sprinkler clearance and racking approval.

What we would want to know before quoting

• Chiller or freezer, and the operating temperature.
• Whether it is a food environment, and how the room is cleaned.
• The slab build-up drawing, and whether the floor has frost protection.
• Internal dimensions and clear height, and where the evaporators are.
• Pallet type and heaviest pallet weight.
• Whether the room can be brought up to temperature, or must stay running.
• Truck type and whether the drivers work inside the room.

We publish a per-bay range for selective racking — S$380 to S$1,200 depending on height, beam length and class — because that is a real, ordinary product. Cold storage is quoted after we have the answers above, because the finish specification, the fixing arrangement and the installation conditions move the figure far more than the steel does.

Send us the room

Temperature, dimensions, the slab drawing if you have it, and whether it has to keep running. We will tell you what needs establishing before a layout is worth drawing — and if the floor is the constraint, we would rather say so at the start.

WhatsApp 9107 2601 about cold room racking →

Related reading: relocating racking to a new warehouse · ramp-up warehouses and floor loading · the racking inspection checklist