Smart building terms,
defined plainly.
Every term you'll hear in a BMS + IoT project. With one-line definitions and a note on when it actually matters.
The vocabulary you'll need.
Updated as we ship new projects. Suggestions welcome.
BACS (Décret BACS)
French decree mandating Building Automation & Control Systems for tertiary buildings > 290 kW (extending to > 70 kW by 2027). Requires actual metered data, not estimates.
BACnet
Building automation protocol used by HVAC, lighting, and BMS vendors. Common in commercial HVAC. Plays well with new IoT via gateways.
BMS (Building Management System)
The centralized system that supervises HVAC, lighting, and energy. Often vendor-locked. Often older than the building owner expects.
Cold chain
Continuous temperature monitoring of perishable goods — vaccines, food, biologics. Auditors want tamper-evident logs, not spreadsheets.
Digital twin
A live data model of a building or process. Useful only if the underlying sensors are reliable. Often sold before the data layer is ready.
EED Article 9
EU Energy Efficiency Directive clause requiring per-tenant sub-metering in multi-unit residential buildings. Implemented differently per country.
EPBD
EU Energy Performance of Buildings Directive. The umbrella behind BACS, ESG reporting, and most national energy mandates.
GMP / HACCP / ISO 13485
Quality standards for pharma, food, and medical devices. They all require documented, tamper-evident environmental monitoring.
HVAC
Heating, Ventilation, Air Conditioning. The biggest energy consumer in most commercial buildings. The most common automation target.
IAQ (Indoor Air Quality)
CO&sub2;, VOCs, humidity, particulates. Tenant satisfaction battleground. Increasingly part of ESG reporting.
IoT
Internet of Things. In buildings: wireless sensors talking over LoRaWAN, NB-IoT, BLE, or WiFi. Cheap to deploy, complex to integrate.
LoRaWAN
Long-range, low-power wireless protocol. Best for sub-metering, occupancy, and asset tracking. Range: hundreds of meters indoor.
Modbus
Industrial protocol from the 80s. Still everywhere. Wires, baud rates, registers. Old but reliable.
MQTT
Lightweight messaging protocol. The lingua franca of modern IoT. Cheap to scale, easy to integrate.
OPC UA
Industrial protocol for SCADA + manufacturing. Heavyweight, secure, increasingly used in smart building orchestration.
PLC
Programmable Logic Controller. The industrial brain of process lines — galvanization, food processing, manufacturing.
Sub-metering
Metering below the utility meter — per floor, per tenant, per process. Required for fair billing and BACS compliance.
Missing a term you want defined?
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