Ventilation

What does the Ventilation domain measure within the SRI?

The Smart Readiness Indicator (SRI) is a European method to determine how intelligent a building's technical systems are. The Ventilation domain examines six smart-ready services that together establish whether a building ventilates based on demand.

Demand-controlled ventilation means the system adjusts the air volume to the actual use of a space. More occupants or higher CO2 concentration trigger increased air supply, and vice versa.

Which services belong to this domain?

Service V-1a regulates supply air flow at room level, from manual control to local demand control with zone-specific valves. Service V-1c does the same at the air handling unit level, the central device that processes air for multiple rooms.

V-2c and V-2d respectively regulate heat recovery and supply air temperature. Heat recovery means warmth from exhaust air is used to preheat incoming air.

V-3 describes free cooling with a mechanical ventilation system, where outside air is used to reduce mechanical cooling demand. V-6 addresses reporting of air quality to users, including alerts for maintenance or necessary actions.

How do the functionality levels progress?

Each service has functionality levels ranging from 0 to 4. Level 0 typically represents no automatic control or manual operation only.

The highest levels add sensors, predictive control, or local valve regulation. For V-1a, this means local demand control per zone based on air quality sensors, with valves that regulate flow for each room.

For V-3, the highest level is control that responds to temperature and humidity together, also called enthalpy-based control. This delivers the most precise balance between air quality and energy use.

Why does this domain count within the SRI?

Ventilation affects both energy consumption and indoor air quality and user comfort. Both aspects are part of the impact criteria the SRI methodology uses to weight domains.

Buildings with installations above 290 kW are expected, through a delegated act from the European Commission, to be required to have SRI assessment. Ventilation forms one of nine domains tested in this process.