# Facilities and Thermal Management A data hall is a building that participates in the computation. Its thermal capacity sets the density that can be installed, its mechanical continuity sets how long that density can be sustained, and its monitoring determines whether an operator sees a developing problem or an alarm. The facility is not a container for the computer; at this density it is part of the computer. > [!note] The one-sentence version > The building decides how much compute can actually run in it, and for how long without interruption. ## What the layer contains **The shell and the halls.** Floor loading for racks in the region of seven thousand pounds, clear height for overhead distribution, fire compartmentation, and a layout that lets blocks be built and commissioned independently; see [[wiki/Data Center Shell|Data Center Shell]] · [[wiki/Structural Steel|Structural Steel]] · [[wiki/Concrete in Data Center Construction|Concrete in Data Center Construction]]. **The thermal chain.** Capture at the silicon, transfer to the facility loop, rejection to the atmosphere, with the air-cooled residue handled alongside; see [[wiki/Data Center Cooling|Data Center Cooling]] · [[wiki/Cold Plate|Cold Plate]] · [[wiki/Direct-to-Chip Liquid Cooling|Direct-to-Chip Liquid Cooling]] · [[wiki/Coolant Distribution Unit|Coolant Distribution Unit]] · [[wiki/Rear-Door Heat Exchanger|Rear-Door Heat Exchanger]] · [[wiki/Air Cooling|Air Cooling]] · [[wiki/Chilled Water Plant|Chilled Water Plant]] · [[wiki/Cooling Tower|Cooling Tower]]. **Water and its alternatives.** Supply, treatment, consumption, discharge, and the dry and hybrid designs that reduce consumption to very little; see [[wiki/Data Center Water Use|Data Center Water Use]]. **Heat as a product.** Warm-water capture makes the facility's output useful to a neighbor rather than discarded; see [[wiki/Heat Reuse|Heat Reuse]]. **Fire protection.** Detection, suppression appropriate to electrical and battery occupancies, compartmentation, and the specific requirements that apply to energy storage rooms; see [[wiki/Data Center Batteries|Data Center Batteries]]. **Monitoring and control.** Building management and electrical power monitoring systems, instrumented so that temperature, flow, pressure, power, and leak detection are visible continuously and correlated with what the computers are doing; see [[wiki/Observability|Observability]]. **Physical security.** Layered perimeter, access control, surveillance, and procedure; see [[wiki/Data Center Security|Data Center Security]]. ## The two principles worth carrying **Thermal continuity is more urgent than electrical continuity.** A liquid-cooled hall loses margin within seconds of flow stopping, so pumps, coolant distribution units, and controls are carried on uninterruptible power and backed by thermal storage, and loops are valved so any element can be isolated while the rest runs. **Capture temperature governs everything downstream.** Capturing heat warm rather than cold removes the compressors from everyday service, cuts water consumption, improves efficiency, and makes the heat valuable to somebody else. It is a single design decision with consequences in energy, water, cost, and community relations at once, which is why it is the first question to ask of any facility design; see [[wiki/Power Usage Effectiveness|Power Usage Effectiveness]]. ## Relationships - **composed of:** [[wiki/Data Center Shell|Data Center Shell]] · [[wiki/Data Center Cooling|Data Center Cooling]] · [[wiki/Chilled Water Plant|Chilled Water Plant]] · [[wiki/Cooling Tower|Cooling Tower]] · [[wiki/Data Center Water Use|Data Center Water Use]] · [[wiki/Data Center Security|Data Center Security]] - **paired with:** [[wiki/Electrical Supply and Reliability|Electrical Supply and Reliability]] - **constrains:** [[wiki/Data Center Rack|Data Center Rack]] · [[wiki/Rack-Scale Computing|Rack-Scale Computing]] · [[wiki/Utilization|Utilization]] - **validated by:** [[wiki/Commissioning|Commissioning]] - **built by:** [[wiki/Pipefitting and Mechanical Trades|Pipefitting and Mechanical Trades]] · [[wiki/Data Center Workforce|Data Center Workforce]] - **source articles:** [[articles/Vertically Integrating an AI Superpower from AI Factory to Citizen|Vertically Integrating an AI Superpower from AI Factory to Citizen]] · [[articles/The Gigawatt Is the New Measure of War|The Gigawatt Is the New Measure of War]] - **collection route:** [[collections/American Infrastructure|American Infrastructure]] · [[collections/American|American Collection]] ## Evidence posture - **Established:** the facility layer's composition of shell, thermal chain, water systems, fire protection, monitoring, and physical security; the seconds-scale thermal margin of a liquid-cooled hall after flow loss and the uninterruptible support and thermal storage that answer it; valved loop isolation; the dependence of compressor hours, water consumption, efficiency, and heat value on capture temperature. - **Established (datestamped):** as of October 2026, facility disclosures across the industry confirm redundant critical power and cooling in independent A and B configurations with facility monitoring, surveillance, and fire suppression as standard practice. ## Sources - ASHRAE data center design guidance and fire and electrical code requirements for data center occupancies, as current October 2026.