Decoding Data Center Prefabrication: From Data Hall to MEP to Shell and Core

December 16, 2025

James Soh

A modern data center showcasing rows of servers in a high-tech environment.

If you've ever been confused by terms like "containerized data center," "prefabricated module," "skids," or "prefab data halls," you're not alone. The data center industry uses these terms inconsistently, creating significant ambiguity for professionals trying to understand what vendors are actually offering. Adding to the confusion, vendors from construction fields (prefabricated walls, beams, columns), cement suppliers, electrical manufacturers/integrators, and container shipping suppliers like CIMC all bring their own interpretations based on their industry background. Plus, shipping containers are actually unsuitable for use in a data center, which I explain near the end of this article. One hint, shipping containers' exterior surfaces are meant to rust.

After years working on data center projects across Southeast Asia, I've realized the problem isn't that we lack terms—it's that we lack a consistent framework for understanding what's actually being prefabricated. The solution is simpler than you might think: take an inside-out view, starting from the data hall and working outward through the MEP infrastructure to the shell and core.

Layer 1: The Data Hall Core

Interior view of prefabricated data hall modules placed in a data hall

The innermost layer is the data hall itself—the IT environment where servers, storage, and networking equipment operate. Prefabrication at this level means factory-assembled enclosures containing racks, aisle containment systems, cable management, in-row cooling, and basic PDUs ready for IT equipment installation.

Containerized data centers represent the most complete version of this layer, where a standard ISO shipping container (20' or 40') becomes a fully integrated data hall with everything needed for operation. These all-in-one units include IT racks, power distribution, cooling systems, and fire suppression in a single portable enclosure.

Prefabricated data hall modules take a larger-scale approach—factory-built rooms or halls complete with raised floors, ceiling systems, fire suppression, and environmental controls, delivered as complete enclosures. Unlike containers constrained by shipping dimensions, these modules can be significantly larger and customized.

Transport of large non-standard size module

Layer 2: MEP Infrastructure

Moving outward, the MEP (mechanical, electrical, plumbing) layer provides power and cooling to the data hall. Prefabrication here means skid-mounted or modular systems assembled and tested in factories before site installation.

Power modules include switchgear, transformers, UPS systems, backup generators, and power distribution units mounted on structural frames. These skids arrive factory-tested and commissioned, ready for connection to utility power and the data hall. Cooling modules contain CRAC/CRAH units, chillers, cooling towers, pumps, and piping systems similarly pre-assembled and tested.

Skids differ fundamentally from containers—they're component systems on frames without enclosing walls, designed for installation into existing buildings or purpose-built MEP rooms. They offer flexibility in sizing beyond shipping container constraints and are particularly suited for large indoor deployments where weather protection isn't needed during operation.

Layer 3: Shell and Core

The outermost layer is the building structure itself. Prefabrication at this level means precast concrete panels, steel framing systems, floor slabs, exterior walls, and roofing systems manufactured off-site and assembled on-site.

Some vendors offer fully prefabricated building envelopes—essentially complete data center "boxes" where even the structural walls, roof, and foundation elements arrive pre-built. These represent the highest degree of prefabrication, where the shell and core, MEP systems, and data hall are all integrated. 

Note on "Containerized" vs. Shipping Containers

A common misconception: legitimate containerized data centers don't use standard ISO shipping containers. Shipping containers are designed for temporary transport—their steel surfaces are treated to withstand cargo shipping, but are expected to rust over time. They also face structural issues when cut for penetrations, poor thermal insulation, condensation problems, and dimensional constraints that limit rack density.

Purpose-built containerized data centers from vendors like Huawei, Schneider Electric, EPG, Vertiv or even CIMC (note that they are well known for marine shipping containers) use custom enclosures with marine-grade corrosion-resistant materials, proper insulation, structural reinforcements for permanent installation, and optimized dimensions beyond ISO constraints. They only superficially resemble shipping containers. 

Practical Application

Understanding which layers can be prefabricated is only the first step. The optimal configuration depends entirely on your specific business requirements—and importantly, prefabrication isn't automatically cheaper or faster.

Prefabrication typically carries higher costs. Testing and commissioning, especially for MEP modules, occurs both at the factory and then again to some extent at the site, thereby increasing costs. Additionally, the business needs around speed of deployment, scalability, space constraints, capacity, and cash flow drive the decision.

General (main) contractors may not be knowledgeable or capable of handling parallel phases where the prefabricated modules or skids are to be hoisted and moved into the halls and rooms while construction activities are still ongoing, thereby negating time saved. There is also planning for the placement of tower and mobile cranes to hoist these modules into place. The logistics planning, storage, and many more unseen factors need to be considered.

Consider these key factors:

• A remote site with limited skilled labor (like the initial Johor data center projects) may justify full prefabrication despite higher costs due to logistics and labor constraints.

• An urban site with readily available contractors might benefit from traditional construction with selective prefabrication of complex MEP systems only.

• A hyperscale deployment requiring rapid capacity addition might use prefabricated data hall modules within traditionally constructed buildings to balance speed and cost.

• A small edge deployment might choose fully containerized solutions for transportability and standardization.

By thinking inside-out—from data hall to MEP to shell and core—you can evaluate any vendor's offering clearly. Instead of getting lost in terminology like "modular" or "prefab," ask which specific layers are factory-built and which remain conventionally constructed. This clarifies exactly what you're buying and deploying.

Understanding the limitations and benefits of each form factor helps ensure the optimal approach is selected based on your project's financial constraints, timeline requirements, site conditions, and local labor availability—not just adopting a vendor's one-size-fits-all solution.

By thinking inside-out, from data hall to MEP to shell and core, we can finally have clearer conversations about prefabrication that acknowledge both its genuine value and its real costs.

Resources

For further reading on prefabricated and modular data center approaches:

• Schneider Electric White Paper: "Understanding the Types of Prefabricated Modular Data Centers" - https://www.datacenterknowledge.com/modular-data-centers/understanding-the-types-of-prefabricated-modular-data-centers

• Uptime Institute TIER-Ready Certification Program for prefabricated data center modules

• ANSI/BICSI 002-2014: Data Center Design and Implementation Best Practices

• ISO/IEC 22237 series: Information technology - Data centre facilities and infrastructures