A cold storage facility is two buildings in one. There is the structure, and there is the thermal envelope and refrigeration system that has to perform inside it for twenty years. Most commercial builders can deliver the first. The gap between the two is where cold storage projects lose money, and a Design and Construct model exists to close it.
What is a “Design & Construct” approach in cold storage?
In a Design and Construct model, one contractor carries responsibility for both the design outcome and the built result. For a warehouse or an office fitout that mainly removes a commercial risk: fewer variations, one point of accountability, no argument about whether a problem is a design fault or a construction fault.
In cold storage it does something more specific. It puts the refrigeration design and the building design in the same room at the same time, under one party who has to make both work.
That matters because in a cold storage facility the building and the refrigeration system are not separate scopes that meet at handover. The slab design depends on the room temperature. The structural loads depend on the panel and racking layout. The electrical capacity depends on the plant selection. The plant selection depends on the thermal load, which depends on the insulation, the door schedule, the door opening frequency, and how the client actually intends to operate the facility.
Change any one of those and the others move. In a fragmented delivery model, they move at different times, priced by different parties, and usually after something has already been built.
Why standard commercial builders fall short on refrigeration infrastructure
This is not a criticism of commercial builders. It is a structural problem with how the scope is normally split.
A refrigeration contractor’s quote covers what a refrigeration contractor controls: panel supply and installation, doors, the refrigeration system and its commissioning, mechanical and electrical work within the system, the evaporator drain to tundish, internal coving and panel sealing, internal lighting, and the safety items the NCC requires for refrigerated rooms.
Look at what a standard refrigeration scope excludes, and the picture becomes clear:
- Mains power and mains plumbing
- Slab setdowns, concrete topping, and floor finishes
- Fire rating
- Penetrations through the building fabric
- Clash detection
- BMS integration
- Coordination with other trades’ finishes and sealing to other trades
Every one of those items is essential to a working cold room. None of them sit with the refrigeration contractor. In a traditional model they land with a builder who priced the job from an architectural drawing set and did not know the setdown depth, the plant electrical load, or the drainage requirement until the refrigeration contractor was appointed, which is often after the slab was poured.
That is where the cost comes from. Not from the refrigeration, which is usually priced accurately, but from the coordination gap around it. A slab poured without a setdown means a raised threshold, a ramp, and a forklift access problem the client will live with for the life of the building. Switchboard capacity discovered late means an upgrade, a Western Power application, and a program delay. A penetration nobody allowed for means cutting a structural element and an engineer’s inspection.
None of those are refrigeration problems. They are all cold storage project problems, and the reason a Design and Construct contractor with in-house refrigeration capability prices them differently is that they are visible before the slab is poured rather than after.
Key stages of a cold storage facility build
Feasibility & thermal efficiency planning
The first question is not how big the rooms are. It is what is going into them, at what temperature, at what turnover, and what the operation looks like on its busiest day.
Thermal load is driven by product load, air infiltration, lighting, people, equipment, and the ambient conditions outside the envelope. In Perth the ambient side of that calculation is not trivial. A plant selection that is comfortable in a mild climate is marginal in February, and a facility that cannot hold temperature during a heat event at peak throughput is a facility that will be running its plant continuously and paying for it.
Getting this stage right sets the panel specification, the plant capacity, the electrical supply requirement, and the slab design. Getting it wrong is expensive to correct because every one of those decisions is downstream of it.
Feasibility should also test the building itself. Floor-to-underside height dictates whether the panel and racking layout works. Existing slab condition and level dictate what the floor build-up will cost. Incoming power capacity dictates whether an upgrade is needed. Vehicle access and turning circles dictate the dock design. Any of these can move a project’s budget materially, and all of them are knowable before design starts.
EPS-FR & PIR panel selection (insulation metrics)
Insulated panel is not a commodity, and the selection is a genuine engineering decision rather than a supplier preference.
EPS in fire-retardant grade is the volume standard across Australian commercial cold storage. It delivers reliable thermal performance at a cost that works, and for the majority of coolroom and freezer applications it is the correct answer.
XPS offers higher compressive strength and lower moisture absorption. Where a panel is taking load or is exposed to persistent moisture, that difference is worth paying for.
PIR delivers the best thermal performance per millimetre of thickness and better fire performance. Where a facility has a fire rating requirement, an insurer requirement, or a footprint constraint that makes thinner walls valuable, PIR earns its cost.
Thickness follows temperature. A coolroom running at 2 to 4 degrees is typically 100mm. A freezer running at minus 18 to minus 20 is typically 150mm. Those are starting points, not conclusions, and a high-duty or unusually large room can require more.
The decision that gets made badly is specifying the cheapest panel that satisfies the thermal calculation without testing it against fire requirements, insurer conditions, washdown exposure, or forklift traffic. Where forklifts and pallet jacks operate, internal wall protection in checker plate wainscot and bump rail is not an upgrade. It is the difference between a panel that survives ten years and one that is punctured in the first year, at which point the insulation is wet and the thermal performance is gone.
Floor slab design: insulation, heater cable and frost heave
This is the single most common expensive mistake in freezer construction, and it is invisible until it is structural.
A freezer holding minus 18 degrees against a ground-bearing slab does not stop at the slab. The cold travels down. Ground moisture beneath it freezes, expands, and lifts. Over time the slab heaves, the floor goes out of level, panel joints open, doors stop sealing, and the correction requires taking the room out of service and rebuilding the floor.
The fix is designed in, not retrofitted. A freezer floor needs an insulated floor build-up to slow the heat loss downward, and heater cable beneath it to hold the ground above freezing. The insulation alone does not solve it. It reduces the rate at which the ground cools, but over the life of the facility the ground still drops below zero, which is why the heater cable is the part that actually prevents the heave.
Both have to be resolved at slab design stage, because both sit within a setdown, and a setdown has to be formed before the pour.
That single dependency is a good test of whether a delivery model is working. If the party designing the refrigeration is appointed after the slab is designed, the answer will be a raised floor, a ramp, lost headroom, and a permanent operational compromise. Coolrooms above zero generally sit on the ground slab without this issue, which is exactly why the distinction has to be settled early rather than assumed.
Integrating complex mechanical services
Plant room positioning & pipework layouts
Plant room location is treated as a leftover decision on a lot of projects. It should be an early one.
Pipe runs between the plant and the evaporators carry a real cost in materials, labour and refrigerant charge, and a real performance penalty in pressure drop and heat gain. Long runs cost more to install and more to operate, permanently.
Plant also needs airflow, service access, noise separation from neighbouring tenancies and boundaries, and a route for condensate drainage. Where the plant is external, condenser positioning has to account for the local environment. In coastal and marine-exposed parts of Perth, condenser coils corrode, and either protective treatment at installation or a servicing regime that manages it is required. Ignore that and the plant fails early.
Every one of those constraints is easier to satisfy on a drawing than on a built structure.
Redundancy planning for temperature-critical stock
The question a cold storage design has to answer is simple: what happens when a compressor fails on a Friday night.
The answer depends entirely on what is in the room. A hospitality coolroom losing temperature for six hours is an inconvenience. A freezer holding a week of processed product, or a facility holding stock with a regulated cold chain requirement, is a different order of exposure. In that case the value of the stock in a single room can exceed the cost of the redundancy that would have protected it.
Redundancy is a commercial decision, not a technical default, and it should be made by the client with the numbers in front of them. The options run from multiple compressors on a common system so that a single failure reduces capacity rather than eliminating it, through to split systems serving separate rooms, through to full standby plant.
What is not optional is monitoring and alarms. A facility that cannot tell an operator that a room is drifting out of range at 2am has no protection at all, regardless of what plant is installed. Automated temperature monitoring with out-of-hours alerting is the cheapest risk control on the project.
Navigating compliance and local WA regulations
Cold storage sits across several compliance streams, and they are administered by different authorities on different timelines.
Building approval
Structure, fire, access and energy provisions under the NCC, through the building surveyor and local government. Insulated panel construction attracts specific attention on fire performance, and insurer requirements can be more demanding than the code minimum.
Food safety
Where the facility stores or handles food, the Food Act 2008 (WA) and Food Regulations 2009 (WA) apply, administered by the local government Environmental Health Officer. This drives finishes, coving, drainage, washdown provisions and the ability to clean the space properly. Facilities handling meat or export product carry further requirements again.
Trade waste
Washdown areas and floor waste discharging to sewer require a Water Corporation trade waste consent. The sizing and location of any pre-treatment has to be resolved before the drainage is set in the slab.
Refrigerant handling
Work on refrigeration systems requires appropriately licensed technicians under the Commonwealth refrigerant handling scheme, and system design has to satisfy the applicable safety standards for refrigerating systems.
Electrical supply
A facility with significant refrigeration load frequently needs a supply upgrade. Western Power applications run on their own timeline and are not responsive to construction pressure, which makes early confirmation of available capacity one of the highest-value checks on the project.
The pattern across all of these is the same. Each has a lead time, each has a hold point, and each is cheap to satisfy at design stage and expensive to satisfy after construction has started.
The ECI advantage: how early contractor involvement protects your budget
Early Contractor Involvement means bringing the builder in during design rather than after it, so that the design is tested against buildability, cost and program while it can still be changed.
For cold storage the value is concentrated in a small number of decisions that are effectively irreversible once construction begins:
- Slab setdowns and the freezer floor build-up
- Incoming electrical capacity and the switchboard position
- Plant room location and the pipe routes to it
- Drainage falls, floor waste positions and trade waste pre-treatment
- Panel specification against the fire and insurer requirements
- Structural capacity for racking loads and panel support
- Dock levels and vehicle access geometry
Each of these is inexpensive to resolve on a drawing. Each is expensive, and sometimes impossible, to resolve after the slab is poured or the structure is up.
ECI also produces a cost plan built from an actual delivery methodology rather than from rates applied to an area. The client gets a number they can rely on and a clear view of the assumptions behind it, at the point where the design can still be adjusted to suit the budget instead of the budget being adjusted to suit the design.
Case Study: Warehouse conversion to long-term cold storage, Northbridge
| Field | Detail |
|---|---|
| Location | Northbridge, Western Australia |
| Building | 1,607m² existing warehouse |
| Delivery | Design and Construct, Lump Sum |
| Duration | 6 months |
| Refrigeration | Lazco, cold storage and refrigeration |
Zera Projects is converting a 1,607m² Northbridge warehouse into a long-term cold storage facility, with responsibility for approvals, infrastructure upgrades, construction and the cold storage and refrigeration fitout under a single contract.
The scope is staged. Stage 1 delivers 100m² of coolroom and freezer room storage. Stage 2 adds a further 450m² of freezer room storage. Alongside the cold storage scope, the project includes a full office fitout and upgrades to the site’s power, hydraulic and mechanical services infrastructure.
The staging is the point. Rather than delivering the full facility before the client can use any of it, the program was structured so that Stage 1 reaches completion and becomes operational while Stage 2 construction continues. The client gets partial use of the facility, and revenue from it, months earlier than a single-stage program would have allowed.
Converting an existing warehouse to cold storage is a different exercise to building one. The existing structure, slab, incoming services and access all have to be assessed against what the finished facility needs, and the gaps priced as infrastructure upgrades rather than discovered as variations. That assessment is what a Design and Construct model is for, and it is the reason the power, hydraulic and mechanical upgrade scope sat inside the contract from the start rather than arriving during construction.
Refrigeration and cold storage are delivered through Lazco, giving the project direct access to specialist capability inside the delivery team rather than at the end of a subcontract chain.
Final thoughts
Cold storage projects are not won or lost on the refrigeration equipment. The equipment is well understood and reliably priced. They are won or lost on the decisions made before construction starts, about slab design, electrical capacity, plant location, panel specification and staging, and on whether one party is accountable for the interface between the building and the system that has to work inside it.
If you are planning a cold storage facility, a conversion, or an expansion, we are happy to look at it with you early, while the decisions that matter are still open.