Why data centre costs are measured in $/MW, not $/m²
In most buildings, floor area tells you the cost. In a data centre it does not — the plant does. That is why the industry prices by the megawatt.
Measure most buildings by the square metre and you get a fair sense of cost. Data centres are different: what drives their cost is the mechanical and electrical (M&E) plant, not the floor. Comparing a colocation data centre with an ordinary industrial building shows why.
The plant dominates
In an industrial building, roughly 90% of the area is useable and only ~10% is plant. In a colocation data centre it flips: around 60% goes to M&E plant and support spaces, leaving ~40% useable whitespace. The cost split is starker still — a data centre puts 70–80% of its budget into M&E plant, against 20–30% for the building itself.
Why $/MW wins
Because the plant is such a large share of both space and cost — and because that plant scales with IT load rather than floor area — the megawatt is the metric that actually tracks what you are paying for. Measuring a data centre in $/m² tells you about the building; measuring in $/MW tells you about the data centre.