MUM-1 is the oldest building on Iron Mountain’s Navi Mumbai campus: 50,000 square feet — 4,645 square metres — Tier III designed, in service since 2015, described by the operator as one of India’s busiest data centres. It publishes 2.5 MW of IT capacity, scalable to 4 MW. In this registry it is flagged additive and contributes nothing, because the source field was left blank when the capacity was not on the page the record was built from. That single blank is a fifth of the company’s energised Indian capacity, and the page exists to show what a missing field costs.
1At a glance
22.5 megawatts the file counts as zero
This is a small building with a large lesson attached to it, so the lesson goes first.
| Field | In this registry | On the operator page | Consequence |
|---|---|---|---|
| Capacity | blank | 2.5 MW | Contributes nothing to any total |
| Additive flag | YES | — | The record is supposed to add |
| Floor area | 50,000 sq ft | 50,000 sq ft | Reconciles exactly |
| Scale ceiling | not recorded | 4 MW | A 1.5 MW upside is invisible |
| Design standard | Tier III | Tier III-designed | Reconciles |
| In-service date | not recorded | 2015 | Age is not visible |
An additive flag of NO tells a reader the row is a rollup and should not be summed. An additive flag of YES with a blank capacity tells a reader the row should be summed and silently isn’t.
Both produce the same arithmetic. Only one of them produces a wrong number that nobody notices.
Three records in the Iron Mountain family carry this combination — MUM-1, MUM-2 and NCR-1 — and between them they hide 8.8 MW of published capacity. That is the whole reason the platform’s 11.5 MW counted figure is 57% of its 20.3 MW published figure.
| Comparison | MW | MUM-1 relative to it |
|---|---|---|
| MUM-3, the building next door | 85 | MUM-1 is 2.9% of it |
| NTT Mumbai 9, the largest operating building in the registry | 62 | MUM-1 is 4.0% of it |
| AirTrunk HYD1, the largest single site in the file | 243 | MUM-1 is 1.0% of it |
| Nxtra Chennai 1, comparable vintage and role | 2 | Roughly the same size |
| The whole 2,420.4 MW registry | 2,420.4 | MUM-1 is 0.10% of it |
Two and a half megawatts is a real building with real customers, and it is also a rounding error in a market where a single new building is 85 MW. Both things are true. The registry’s job is to keep 2.5 MW visible rather than let it fall out of a total because of a blank cell.
3Fifty thousand square feet, fifty watts a foot
MUM-1 is the least dense per square foot of the buildings where this registry can compute density, and the comparison is instructive because it dates the design era.
| Building | MW | Floor area | Watts per sq ft |
|---|---|---|---|
| MUM-2, 2023 | 6.3 | 110,631 sq ft | 56.9 |
| MUM-1, 2015 | 2.5 | 50,000 sq ft | 50.0 |
| BLR-1, Bengaluru | 4.0 | 80,000 sq ft | 50.0 |
| HYD-1, Hyderabad phase one | 5.5 | 120,000 sq ft | 45.8 |
| PUN-1, Hinjewadi | 2.0 | 50,186 sq ft | 39.9 |
| MUM-3, at full build | 85 | 1,398,000 sq ft | 60.8 |
| Portfolio weighted average | 20.3 | 480,552 sq ft | 42.2 |
Fifty watts per square foot is normal for a 2015 carrier-neutral building with a traditional raised floor. MUM-3 at 60.8 W per sq ft is not a dramatic increase — and that matters, because it means the megawatts at MUM-3 come mostly from floor area, not from rack density. 1.4 million square feet is what buys 85 MW; the racks inside are only about 22% denser than MUM-1’s.
A building that scales by area needs land, structure and steel. A building that scales by rack density needs power and cooling. They are different supply chains, different risks and different lead times.
MUM-3 is the first kind at campus scale. AirTrunk’s Chandivali at 12.9 MW per acre is the second. Anyone quoting a single per-megawatt construction cost across both is quoting an average of two unrelated things.
4Procurement
5Limits and open questions
- 2.5 MW is IT capacity as published by the operator. Facility load is not stated; at a typical ratio it would be about 3.5 MW.
- The 4 MW figure is scalability, not commissioned load, and is excluded from every total on this page.
- The floor area is a whole-building figure, not technical hall, so 50 W per sq ft understates density inside the halls.
- The in-service date of 2015 comes from the operator page and is not corroborated by an independent announcement.
- The count is zero. This page does not change the registry total; it explains why the total is low.
- What would close it. A capacity value in the source field, and an additive rule that treats a blank as a defect rather than a valid state.
6Sources
Sources: the Iron Mountain MUM-1 location page; the Iron Mountain Mumbai campus page; the Iron Mountain Data Centers India platform page; and the Web Werks MUM-1 facility page.