Jennifer A. Senick

Designing Buildings for Real Occupants: An Agent-Based Approach

Building information modeling is only beginning to incorporate human factors, although buildings are sites where humans and technologies interact with globally significant consequences. Some buildings fail to perform as their designers intended, in part because users do not or cannot properly operate the building, and some occupants behave differently than designers expect. Innovative buildings, e.g., green buildings, are particularly susceptible to usability problems. This paper presents a framework for prospectively measuring the usability of designs before buildings are constructed, while there is still time to improve the design. The framework, which was implemented as an agent-based computer simulation model, tests how well buildings are likely to perform, given realistic occupants. An illustrative model for lighting design shows that this modeling approach has practical efficacy, demonstrating that, to the extent that users exhibit heterogeneous behaviors and preferences, designs that allow greater local control and ease of operation perform better.

Comparison of real-time instruments and gravimetric method when measuring particulate matter in a residential building

ABSTRACT This study used several real-time and filter-based aerosol instruments to measure PM2.5 levels in a high-rise residential green building in the Northeastern US and compared performance of those instruments. PM2.5 24-hr average concentrations were determined using a Personal Modular Impactor (PMI) with 2.5 µm cut (SKC Inc., Eighty Four, PA) and a direct reading pDR-1500 (Thermo Scientific, Franklin, MA) as well as its filter. 1-hr average PM2.5 concentrations were measured in the same apartments with an Aerotrak Optical Particle Counter (OPC) (model 8220, TSI, Inc., Shoreview, MN) and a DustTrak DRX mass monitor (model 8534, TSI, Inc., Shoreview, MN). OPC and DRX measurements were compared with concurrent 1-hr mass concentration from the pDR-1500. The pDR-1500 direct reading showed approximately 40% higher particle mass concentration compared to its own filter (n = 41), and 25% higher PM2.5 mass concentration compared to the PMI2.5 filter. The pDR-1500 direct reading and PMI2.5 in non-smoking homes (self-reported) were not significantly different (n = 10, R2 = 0.937), while the difference between measurements for smoking homes was 44% (n = 31, R2 = 0.773). Both OPC and DRX data had substantial and significant systematic and proportional biases compared with pDR-1500 readings. However, these methods were highly correlated: R2 = 0.936 for OPC versus pDR-1500 reading and R2 = 0.863 for DRX versus pDR-1500 reading. The data suggest that accuracy of aerosol mass concentrations from direct-reading instruments in indoor environments depends on the instrument, and that correction factors can be used to reduce biases of these real-time monitors in residential green buildings with similar aerosol properties. Implications: This study used several real-time and filter-based aerosol instruments to measure PM2.5 levels in a high-rise residential green building in the northeastern United States and compared performance of those instruments. The data show that while the use of real-time monitors is convenient for measurement of airborne PM at short time scales, the accuracy of those monitors depends on a particular instrument. Bias correction factors identified in this paper could provide guidance for other studies using direct-reading instruments to measure PM concentrations.

Energy-efficient reuse of existing commercial buildings

Problem, research strategy, and findings: Increased demand for urban living, financial incentives for redevelopment, and conducive planning regulations are leading to significant commercial building reuse. This trend represents an opportunity to upgrade the energy performance of the existing building stock in older, more walkable downtowns and to achieve preservation goals. Some advocates of building reuse resist imposing the cost of energy improvements on associated projects, while many energy efficiency advocates do not distinguish how the opportunities and constraints differ between new and existing buildings. Building code officials experience this tension when reviewing improvements to existing buildings, and many find that sections of the widely adopted International Energy Conservation Code are pragmatically unenforceable. In this study we examine the existing-building energy challenge using a mixed-methods approach within one region as well as a national-level analysis of governmental data. We characterize promising regulatory strategies including exempting historic buildings (which is the status quo), exempting smaller buildings and less energy-intensive occupancies and systems, and creating simple lookup tables that provide succinct guidance to redevelopers and code officials. Takeaway for practice: Code officials enforce longstanding life-safety codes more assiduously than they do the newer energy codes, and these codes need revisions to make them more cost effective and enforceable. A better understanding and implementation of building energy codes can have positive implications for both energy performance and downtown revitalization. Success depends on better managing interdependencies among the national policy objective of energy efficiency, the ubiquitous local planning objective of downtown revitalization, and the bureaucratic challenges of regulating construction in existing buildings. Planners should bring code officials into adaptive reuse projects early.

Distinguishing between green building occupants’ reasoned and unplanned behaviours

Several frameworks incorporate social and psychological elements of environmentally significant behaviour, and most assume cognitive and deliberate decision-making. Household energy consumption behaviours, however, span a spectrum from reasoned and deliberate to unplanned and automatic. The aim of this paper is to advance knowledge of reasoned and unplanned behaviours in the context of pro-environmental action. Using results of a survey administered to occupants of an urban residential green building, this study explores five household consumption behaviours and tests the hypothesis that unplanned behaviours will be poorly predicted by a reasoned, values-based behavioural framework. Using path analyses, variables in a values-based framework are used to predict surveyed behaviours. Findings indicate that behaviours hypothesized to be unplanned were not well predicted by the values-based framework. The framework successfully predicted what was hypothesized to be a fully reasoned behaviour. Three potential reasons are discussed for the lack of prediction of some behaviours. A deeper understanding of how unplanned, automatic or habitual behaviours intervene in conservation intentions can help policy-makers and building designers better respond to influences of occupant behaviour on building performance.

Airborne Particulate Matter in Two Multi-Family Green Buildings: Concentrations and Effect of Ventilation and Occupant Behavior

There are limited data on air quality parameters, including airborne particulate matter (PM) in residential green buildings, which are increasing in prevalence. Exposure to PM is associated with cardiovascular and pulmonary diseases, and since Americans spend almost 90% of their time indoors, residential exposures may substantially contribute to overall airborne PM exposure. Our objectives were to: (1) measure various PM fractions longitudinally in apartments in multi-family green buildings with natural (Building E) and mechanical (Building L) ventilation; (2) compare indoor and outdoor PM mass concentrations and their ratios (I/O) in these buildings, taking into account the effects of occupant behavior; and (3) evaluate the effect of green building designs and operations on indoor PM. We evaluated effects of ventilation, occupant behaviors, and overall building design on PM mass concentrations and I/O. Median PMTOTAL was higher in Building E (56 µg/m3) than in Building L (37 µg/m3); I/O was higher in Building E (1.3–2.0) than in Building L (0.5–0.8) for all particle size fractions. Our data show that the building design and occupant behaviors that either produce or dilute indoor PM (e.g., ventilation systems, combustion sources, and window operation) are important factors affecting residents’ exposure to PM in residential green buildings.

Synthetic Populations of Building Office Occupants and Behaviors

The goal of this chapter is to convey a novel approach to overcoming the limitations of case study research of building occupant behavior in workplace settings by pooling samples and creating a synthetic population of building occupants and behaviors. Synthetic populations can be used by researchers and designers of buildings to develop more accurate models of performance and behavior (Andrews et al. 2016). In the example presented here, three disparate field studies of workplace settings are combined into a larger database that is enhanced through the generation of a statistically similar synthetic data set.