A Practical Guide Based on a Medium-Scale Factory Deployment
In new factory construction or major facility upgrades, the IT data room is often not considered a primary architectural element. However, it ultimately becomes the operational backbone of all digital systems.
Design omissions at an early stage almost always lead to higher costs, operational risk, and downtime later.
This article summarizes practical planning considerations for an IT data room designed to support four racks, AI/GPU workloads, and enterprise systems, based on real-world engineering discussions rather than theoretical standards.
1. A Data Room Is a System, Not Just a Room
A common misconception is:
“An IT room is simply a space where racks are placed.”
In reality, an IT data room is a tightly coupled system consisting of:
- Electrical power (utility, UPS, generator)
- Cooling and airflow management
- Network and low-voltage infrastructure
- Rack layout and cabling
- Structural load capacity
- Maintenance access and future expansion
Designing any of these in isolation often compromises the entire system.
2. Space Planning: Racks Are Only One Component
For a deployment of four 42U racks, the actual space requirement includes:
- Rack footprints
- Cold and hot aisle clearances
- UPS units and battery cabinets
- Cooling equipment
- Power distribution panels
- Maintenance and replacement access paths
Practical Recommendation
- Total room size: 35–45 m² (approx. 8 × 5 m)
- Implement cold aisle / hot aisle separation
- Allocate space for future growth, not just current equipment
The biggest risk is not oversizing a data room, but building one with no margin.
3. Cooling and Airflow: Heat Must Have a Defined Path
1. Cold and Hot Aisle Fundamentals
- Cold air enters from the front of racks (cold aisle)
- Hot air exits from the rear (hot aisle)
Without airflow control:
- Hot air recirculates
- Cooling efficiency drops sharply
- Equipment temperatures become unstable
2. Where Does the Hot Air Go?
In medium-sized data rooms, a common and effective approach is:
- Ceiling return plenum
- Supply air from floor or low wall
- Hot air rises naturally and is returned to CRAC units
Full hot-aisle containment is optional, but:
- Cold and hot air streams must not mix
- Hot air must be reliably collected and returned
4. Power Architecture: From Utility to Rack
1. The Role of UPS
UPS systems are not intended to provide long-term power. Their purpose is:
- Power conditioning
- Bridging the gap until generator power is stable
In factory environments:
- UPS + diesel generator is the standard design
- Typical UPS autonomy target: 10–15 minutes
2. Why UPS Capacity Is Rated in kVA
- kVA: electrical equipment capacity (current and thermal limits)
- kW: actual usable power
- Relationship depends on power factor (PF)
UPS selection must always be based on usable kW, not kVA alone.
3. UPS Is Not a Power Strip
A critical but often misunderstood point:
The UPS does not directly provide multiple 220V 30A outputs.
The correct power flow is:
Utility / Generator
↓
ATS
↓
Data Room Power Panel
↓
UPS-A / UPS-B
↓
UPS Output Panel
↓
220V 30A Branch Circuits
↓
Rack PDUs
This design enables:
- A/B power redundancy
- Dual-corded server connections
- Fault isolation without service interruption
5. Battery Configuration: Determining Runtime, Not Decoration
UPS specifications often list:
- Standard battery count (e.g., 32 units)
- Optional expansion (up to 40 units)
Battery quantity must be selected based on:
- Actual load percentage
- Generator start-up time
- Risk tolerance
In this case:
- ~80% UPS load
- Generator available
- 40 batteries provide ~10–15 minutes, which is appropriate and cost-effective
6. Weight and Structural Load: A Non-Negotiable Constraint
When combining:
- UPS chassis
- Isolation transformer
- Battery cabinets (40 × 12V batteries)
A single UPS system can exceed 1 metric ton.
With A/B redundancy:
- Total equipment weight may reach 2–3 tons (distributed)
Design Implications
- Floor loading must be reviewed by a structural engineer
- Focus on concentrated load, not average floor loading
- Requirements must be declared during architectural design—not after construction
7. Cable Tray and Routing: The Invisible Infrastructure
Cabling design directly affects:
- Airflow efficiency
- Maintenance safety
- Scalability
Best practices include:
- Separate trays for power and data
- Overhead routing to avoid airflow obstruction
- Reserve 30–50% tray capacity for future expansion
8. The Most Important Responsibility During Design
The IT team’s role is not to produce construction drawings, but to:
Define clear, enforceable, and scalable design requirements.
Resolving issues on paper is far cheaper—and safer—than fixing them inside a live data room.
Conclusion
A well-designed IT data room is not defined by the most expensive equipment, but by:
- Clear power architecture
- Predictable airflow
- Structural safety
- Operational maintainability
- Long-term flexibility
All of these must be addressed during architectural and MEP design, not after systems are installed.
A data room is not just an IT issue—
it is a shared responsibility between architecture, engineering, and operations.