Occupant-Centric key performance indicators to inform building design and operations

Abstract

Highlights Occupant-centric metrics are currently ad hoc and limited, yet crucial to inform building design and operations.  Literature was reviewed to reveal the state-of-the-art and gaps of occupant-centric metrics.  A suite of occupant-centric key performance indicators (KPIs) covering five groups of building services were synthesized.  Proposed occupant KPIs represent three aspects of performance: resource use and demand, occupant comfort and health, and human-building interactions.  A case study using whole building simulation was conducted to demonstrate the use of occupantcentric KPIs in evaluating building operations during a power outage.

Development and Application of Schema Based Occupant-Centric Building Performance Metrics

“…Examples of data schemes include the Industry Foundation Classes (IFC), used to standardize building information model (BIM) data [30], green building XML (gbXML), used to standardize data exchange for BIM to building energy modeling (BEM) applications [31], and BuildingSync, used to standardize data captured by an energy audit [32]. While many of the occupant-centric KPIs were demonstrated using simulated buildings (BEMs) [9,33], it is our opinion that evaluating these KPIs during the operational phase of the building is more valuable. Therefore, we will focus on operations specific building data schemas and only provide a brief introduction to the two of interest.…”

“…The concept of occupant-hour is commonly used in [9] as part of a KPI calculation. Although this is an ideal metric to use in occupant-centric KPIs, it is impractical in the majority of buildings since occupancy counting is still an emerging technology.…”

“…Table 4 describes the different systems and sensing technologies used and also characterizes them according to relevant occupant-centric factors as outlined in [9]. System C demonstrates the installation density of occupancy sensors that is typical for office buildings designed in accordance with the IECC 2015 code cycle.…”

“…Using some of these different methods for measuring occupancy, case study 29 [8] summarizes and compares the annual energy consumption of buildings considering the designed occupant density and measured occupancy counts. The majority of the research regarding occupantcentric metrics and KPIs was recently summarized in [9]. An important observation is that many of these KPIs rely on obtaining an accurate count of people in a building.…”

“…Occupant-centric KPIs that relate building energy consumption to occupancy data have been demonstrated before, such as the energy per occupant-hour [9]. Most of these metrics have been annualized metrics and haven't considered granular occupancy data or energy data, which is now significantly more relevant.…”