LBNL-1004496
Introduction to an occupant behavior motivation
survey framework
Simona D'Oca, Stefano Corgnati, Anna Laura Pisello,
Tianzhen Hong
Energy Technologies Area
February,2016
Introduction to an occupant behavior motivation survey framework
Simona D’Oca#, **1, Stefano Corgnati#2, Anna Laura Pisello*3, Tianzhen Hong**4
#
TEBE Group, Energy Department of Polytechnic of Torino, Italy
Corso Duca degli Abruzzi 24, 10139, Torino (Italy)
[email protected]
[email protected]
*3Department of Engineering, University of Perugia, Italy
Via G. Duranti 93, 06125, Perugia (Italy)
3
[email protected]
**Lawrence Berkeley National Laboratory
1 Cyclotron Rd, Berkeley, CA 94720
4
[email protected]
Abstract
An increasing body of research is underlying the need to foster energy behaviors and
interaction with technology as a way to achieve energy savings in office buildings.
However, engaging office users into more “forgiving” comfort-adaptive behavior is
not a trivial task, since neither consequences nor benefits for changing behavior have
visible or tangible effects on them personally. Since the 70’s, survey studies in the
field of building science have been used to gain better understanding of
multidisciplinary drivers of occupant behavior with respect to comfort and energy
requirements in buildings. Rather than focusing on individual behaviors – and
influencing factors – purpose of this survey research is to provide quantitative
descriptions on the collective and social motivations within the complexity of different
social groups in working environment, under different geographical context, culture
and norms. The resultant questionnaire survey emerges as a combination of traditional
and adaptive comfort theories, merged with social science theory. The questionnaire
explores to what extent the occupant energy-related behavior in working spaces is
driven by a motivational sphere influenced by i) comfort requirements, ii) habits, iii)
intentions and iv) actual control of building systems. The key elements of the proposed
occupant behavior motivational framework are grounded on the Driver Need Action
System framework for energy-related behaviors in buildings. Goal of the study is to
construct an additional layer of standardized knowledge to enrich the state-of-the-art
on energy-related behavior in office buildings.
Keywords: energy-related occupant behavior, questionnaire survey, motivation, DNAs
framework, office buildings
1.
Introduction
In Europe and US, about 40% of the total primary energy consumption derives
from building construction and operation. Specifically, more than 60% of this amount
depends on the energy consumption for heating, cooling, ventilation and lighting,
meaning a huge proportion of world energy consumption is spent to maintain
comfortable and healthy inhabited environments. As demands for low energy
consumption is constantly increasing, architects and engineers are facing great
challenges of saving energy while maintaining or even improving current comfort
levels for occupants. The implications of occupants’ behaviors seeking for comfort
conditions in indoor environments are undoubtedly essential for building energy
requirements.
Recent advancements in energy researches have brought about more awareness of
the importance of the human dimension as part of the energy system. Achieving energy
conservation emerged as a double challenge, partly technical and partly human. Energy
consumption may vary largely due to how occupants interact with system controls
(thermostats, lights, equipment, etc.) and the building envelope (windows, blinds,
shades, etc.) to adapt themselves to the thermal and visual environment.
There is a growing body of research underlying the need to foster energy conscious
behaviors and interaction with technology as a way to achieve energy savings [1-4].
Results from a simulation study to evaluate the impact of occupant behavior on energy
use of private offices [5] demonstrated that occupants with wasteful work-style
consumed up to 90% more energy than standard users, while austerity work-style
occupants used half of the energy of the standard occupants. Accordingly, the
development of energy conservation technologies is a necessary but incomplete step
toward energy efficiency goals and net zero energy buildings. However, it is a
challenging task to develop reliable scenarios of the impact of occupant behavior on
final energy usage due to the stochastic nature of human behavior [6].
It is shown that users allowed to interact with control systems are more satisfied
with their own working environments [7], since they became more forgiving to adapt
themselves to the variation of indoor climate conditions and to tolerate greater
fluctuations in acceptable temperature ranges [8]. In this context, leading building
occupants in workspaces towards comfort-adaptive energy-saving behaviors can be
seen as an effective and low-cost investment [9] to reduce energy consumption by up to
30% [5]. This can be achieved by maintaining comfort condition and increasing
satisfaction and productivity [10]. Yet, in office buildings, engaging users into more
“forgiving” indoor climate conditions [11] – sometime at the expenses of indoor
environmental quality and comfort – is not a trivial task. Differently from the household
context, neither consequences nor benefits for changing behavior (i.e. saving money
from the energy bill) have visible or tangible effects on them personally. For this
reason, it is necessary to achieve a deeper understanding of the motivation structure
towards the concept of “forgiveness” and comfort-adaptive (and energy-saving)
behaviors within the complexity of different social groups in working environment.
The future of occupant behavior studies remains a multidisciplinary and
controversial field [12], since comfort condition and energy use is recognized not
merely related to physical parameters but also factors. In order to fully understand
occupant behavior based on facts rather than hypothesis, there is a need for discovery of
a layer of social, contextual and group interaction constructs related to individual
motivations, which overlap the four key components of the human-building interaction:
i) the Drivers of behavior, ii) the Needs of the occupants, iii) the Actions carried out by
the occupants, and iv) the building systems acted upon by the occupants [13].
Motivation emerged as a key unlocking parameter for behavioral change, as largely
discussed in the field of behavioral science theory [14, 15]. As described in the Theory
of Planned Behavior [16], motivations are driving behavior, and can be assumed as a
proxy to describe actual behavior. Questionnaire studies conducted in the field of
behavioral studies [17-18], also confirmed motivation can be assumed to be the
immediate antecedent of behavior. Building occupant behavior research commonly
focuses on direct observations such as sensor or other non-self-report data. In contrast,
social science research generally deals with self-report data or latent variables such as
motivations, beliefs, perceptions, emotions, and attitudes. To the extent that perceived
behavioral control communicated by the questionnaire respondents is veridical, it acts
as a latent variable for actual control and can contribute to the prediction and estimate
of the behavior in question. Social science provides quantitative methodological
descriptions on how to develop survey researches related to human subjects [19]. Since
the 70’s, a wide spectrum of building science researches started dealing with the
variables of occupants’ comfort satisfaction, need, acceptance and energy concerns.
Yet, surveys have been widely used to gain a better understanding of occupant behavior
and comfort requirements in office buildings, as reviewed in Ackerly et al [20].
2.
Methodology
The purpose of this survey research is to provide standardized quantitative
descriptions on the motivations driving occupant behavior in office buildings. Rather
than focusing on individual behaviors and influencing factors, key results aim to be
generalized under collective and social conventions shaped by geographical and
climatic contexts, culture and norms.
Adaptive
Pshycological
Social
Contextual
Occupant behavior theory
(Humphrey et al)
Questionnaire surveys
(Ackerly et al)
habits
comfort
Comfort theory
(Fanger)
(De Dear & Brager)
Physical environment
Physiological parameters
DRIVERS
SYSTEMS
NEEDS
ACTIONS
Awareness of consequences
Situation responsibility
Attitude
Efficacy
Norm activation theory
(Harland et al)
Theory of planned behavior
(Aizen et al)
intentions
control
Social practice theory
(Brown et al)
Figure 1. Structure of the OB Motivation Framework
Knowledge
Ability
Technology
The survey structure is primarily grounded on the DNAS ontology for energyrelated occupant behavior in buildings [13]. In this framework, the goal of the study is
to create an additional layer of standardized knowledge on energy-related behavior in
office buildings, to enrich the state-of-the-art. The resultant self-report questionnaire is
a combination of key questions emerged in a comprehensive literature review of
occupant behavior questionnaire surveys [20], Humphreys’ principle of occupant’s
interaction with control systems in buildings [21], traditional [22] and adaptive comfort
theories [23] merged with social science theories [15-18, 24]. The questionnaire
explores to what extent the occupant energy-related behavior in working spaces is
driven by an individual motivational sphere influenced by i) comfort requirements, ii)
habits, iii) intentions and iv) actual control of building systems (Table 1)
Table 2. Structure of the OB Motivation Survey Framework
Habits
Comfort
Section
Context
physical environment
physiological parameters
adaptive
phsychological
social
Control
Intentions
contextual
awareness of
consequences
situation responsability
attitude
efficacy
knowledge
ability
technology
3.
Focus Area
thermal comfort
visual comfort
IAQ
gender
age
past behavior
response automaticity
social norms
workstyle routine
empolyment role
country of origin
enviromental factors
References
perceived subjective norms
Onwezen at al, 2013 [15]
Ajzen et al, 2001 [16]
Harland et al, 2007 [17]
Stern et al, 1986 [18]
perceived social norms
perceived willingness
perceived effectiveness
perceived control
actual control
perceived access
perceived impediments
perceived achievements
Brager et al, 2004 [23]
Fanger, 1987 [22]
Ackerly et al, 2012 [20]
Humphreys et al, 1995
[21]
Brown et al, 2009 [24]
Results
As the first step towards the development of the motivational framework, a field
survey structure is settled in order to understand the predictor variables leading
occupants to adapt to and to accept more rigid comfort conditions reducing or not
relying on the mechanical control systems in offices.
The occupant motivation survey is structured into the following 4 sections,
corresponding to the framework structure. For each section, the questionnaire defines i)
the context of the question and allocates distinct ii) focus area categories, and provides
background references, as follows:
1.
Comfort (Table 2)
a. Physical environment: thermal comfort; visual comfort; acoustic comfort; IAQ
b. Physiological parameters: gender; age
2. Habits (Table 3)
a. Adaptive: past behaviors
b. Psychological: response automaticity
c. Contextual: workstyle routine; employment role; country of origin;
environmental factors
3. Intention (Table 4)
a. Awareness of consequences: perceived subjective norms
b. Situation responsibility: perceived social norms
c. Attitude: perceived willingness
d. Efficacy: perceived effectiveness
4. Control (Table 5)
a. Ability: perceived and actual control; perceived access and impediments
For each of the focus area categories, the questionnaire allocates iii) survey questions
and specifies iv) the scale or the options for the questionnaire responses.
Table 2. Comfort Section: Occupant Behavior Motivation Survey Framework
Context
Focus Area
thermal comfort
physical
environment
Survey question
ASHRAE 7 points scale
What's the most frequent
cause for thermal
discomfort?
§ Air draft
§ Floor too cold (cold feet)
§ Too cold during winter
§ Too hot during summer
§ Too aggressive heating during winter
§ Too aggressive cooling during summer
§ Zones at different temperatures
§ Cold nearby windows
Grade your typical visual
comfort satisfaction in your
working space
dissatisfied/satisfied 7 points scale
What's the most frequent
cause for visual discomfort?
§ Improper office lighting
§ Excessive office lighting via natural means
§ Glare on my computer/working plane
§ Lack of view from outside (eye tiredness)
Grade your IAQ satisfaction
dissatisfied/satisfied 7 points scale
What's the main cause for
indoor air quality
discomfort?
What's your gender?
What's your age?
§ Stuffy air
§ Co2 concentration
§ Bad/strong/offensive odors/scents
male/female
cardinal
visual comfort
IAQ
physiological
parameters
gender
age
Scale
Grade your typical thermal
comfort satisfaction in your
working space
The questions and scale/options for self-report responses are designed to comply with
the principles of specificity (qualitative responses) and generality (quantitative
responses) [20]. Insights from social science are borrowed to design a correct order of
the questions to avoid biased effects on the answer of the respondents [19].
Table 3. Habits Section: Occupant Behavior Motivation Survey Framework
Focus Area
Survey question
past behavior
I typically perform these adaptive
actions to make myself comfortable
because:
§ feeling hot (summer)
§ feeling cold (winter)
§ for airing spaces
§ for providing natural lighting
§ for preventing glare
§ for preventing overheating
§ for preventing overcooling
I typically perform these adaptive
opportunities in my working space in
order to:
§ restore my comfort conditions
§ conserve energy
Scale
Context
Adaptive
phsychological
contextual
response
automaticity
workstyle
routine
employment role
country of origin
environmental
factors
social
social norms
Preference of indoor environmental
control in your office space
§ never
§ once a week
§ more than once a week
§ once a day
§ more than once a day
§ opening/closing windows
§ turning up/drawing blinds/shadings
§ turning on/off the heater/cooling when
feeling too hot/too cold
§ using flexible dress code
§ Free manual control (operable windows
and shading, manual heating and cooling set
points)
§ Automatic mechanical control
(mechanical ventilation, automatic shading
and heating and cooling set point)
What's your workstyle schedule?
full time/part time
What's your employment role?
What's your country of origin?
employee, manager, student, professor
nominal
§ Open Space
§ Shared office (max 4 people)
§ Shared office with another person
§ Single office
What's the spatial configuration of
your office?
Do you feel free to dress as you like?
Do you have a formalized dress code
in your office?
How much does the building
management encourage/discourage
these adaptive actions/opportunities?
§ opening/closing windows
§ turning up/drawing blinds/shadings
§ turning on/off the heater/cooling
when feeling too hot/too cold
§ using flexible dress code
How much does the building
management encourage/discourage
flexible dress?
yes/no
§ encouraging
§ don't care
§ discouraging
§ encouraging
§ don't care
§ discouraging
The elements of the questionnaire identify at times a specific action or motivation, by
means of qualitative responses. Other times the generality of the questions is increased
by aggregation of typical behaviors, by means the adoption of unpaired numerical
scales (7 points). These elements constitutes the predictor variables for measuring the
impact of motivational drivers over the likelihood of adopting motivation-driven rather
than adaptive-unconscious interaction with the building control systems, having impact
on energy and comfort requirements.
Table 4. Intention Section: Occupant Behavior Motivation Survey Framework
Context
Focus Area
awareness of
consequences
perceived
subjective
norms
situation
responsability
perceived
social norms
attitude
perceived
willinginess
Survey question
Saving energy in my workspace will cause
me to reduce my comfort level
Reducing comfort in my workspace will
cause me to reduce my productivity
Interacting with the control systems to make
myself comfortable in my workspace will
influence:
§ Energy consumption
§ My comfort level
§ My productivity
I am prone to accept more forgiving indoor
environmental condition to conserve energy
in my workspace:
§ to help my company to reduce budget
costs for energy provision
§ to be visible among my coworkers
§ to be environmentally friendly
Are you willing to use windows/other
devices to make yourself comfortable?
Are you willing to use windows/other
devices to save energy in your workspace?
Which are in your opinion the barriers to
overcome to turn your willingness into a
habit?
efficacy
perceived
effectiveness
Which are for you the benefits of adopting
energy saving behavior in your working
space?
Which type of reward would you willing to
receive, to motivate you towards energy
saving behaviors?
How effective are the adaptive actions in
helping you to stay comfortable?
Scale
very much/not at all 7 points scale
very much/not at all 7 points scale
§ reducing
§ any change
§ augmenting
likely/unlikely 7 points scale
very much/not at all 7 points scale
very much/not at all 7 points scale
§ Lack of time
§ Lack of convenience
§ Technical barriers due to control
system usability issues
§ Technical barriers due to space
layout issues
§ Comfort issues
§ Visibility among employers
§ Visibility of my employers/company
§ Comfort issues
§ Being financially rewarded when
performing energy saving behavior
(peer comparison)
§ Being praised when performing
energy saving behavior (incentives)
§ Receiving negative messages or
criticism when not performing energy
saving behavior (naming and shaming)
very ineffective/very effective 5 point
scale
A selection of statistical models typically adopted for survey data analysis (e.g.
multivariate analysis, frequency distribution analysis, marginal homogeneity test,
Pearson Chi-Square test, Cronbach’s alpha test, likelihood ratio test, correlation
analysis, single and multiple regression models.) and data mining methods (cluster
analysis, decision tree, association rules, etc.) will be applied for the investigation of the
predictor motivational variables. The evaluation of the magnitude of different perceived
control opportunities will establish new knowledge about the motivational sphere
driving decisions of similar profiles of office users’ to engage towards the energyrelated measures under scope of investigation. A wide variety of survey distribution
method and tools are available for survey delivery. To align with the authors’ expertise,
project goals and budget, the open-access and web-based Google Forms will be used.
Table 5. Control Section: Occupant Behavior Motivational Framework questionnaire
Perceived control
opportunity
Survey question
Scale
Context
How would you grade your knowledge in terms of?
§ how is comfort control provided in your workspace
§ who is responsible for comfort controlling in your
workspace
§ very knowledgeable
§ don't care
§ not at all knowledgeable
Who is responsible for controlling?
not at all
knowledgeable/very
knowledgeable
actual control
During the last six months, I performed these adaptive
actions to make myself comfortable:
§ opening window when feeling hot
§ closing window when feeling hot
§ opening window for airing spaces
§ turning up blinds/shadings for providing natural lighting
§ drawing blinds/shadings for preventing glare
§ drawing blinds/shadings for preventing overheating
§ turning on the heater when feeling cold (winter)
§ turning off the heater when feeling too hot (winter)
§ turning on the cooling/fans when feeling hot (summer)
§ turning off the cooling/fans when feeling too cold
(summer)
§ removing/adding extra layers of clothing
§ never
§ once a week
§ more than once a week
§ once a day
§ more than once a day
perceived access
My authority (I am allowed to) to interact with control
systems in my working space is
My ability (I manage to) to interact with control systems
in my working space is
How satisfied are you with your degree of control/ability
to make yourself comfortable?
not allowed/allowed 7 point
scale
no control, full control 7
point scale
very dissatisfied/very
satisfied 7 point scale
What are your main perceived impediments to interact
with the control systems?
§ Access
§ Knowledge
§ No need
§ Upset coworkers
§ Security
§ Outdoor pollutant
perceived control
ability
perceived
impediments
Regarding the sample needed to assure validity and robustness of the survey
question, insights from social science provide a formula to determine the survey
respondent sample size and response rate acceptability, as a function of population sizes
and characteristics at confidence intervals [25]. Another approach is to refer to the
average sample number – about 1000 interviewed – of the occupant survey researches
published in literature.
4.
Discussion and Conclusions
The prospect of comfort theory is still debated as a multidisciplinary and
controversial field [12], since comfort condition is not only related to building physical
and environmental parameters but also to social constructs reflecting beliefs, values,
expectations, and mostly motivation of occupants. The key elements of the proposed
occupant behavior motivational framework are grounded on the DNAS framework for
energy-related behaviors in buildings [13]. The resultant questionnaire is based on
extensive literature review of previously developed occupant behavior surveys [20] and
emerges as a combination of traditional [22] and adaptive comfort [23] theories, merged
with occupant behavior [21] and social science theories [15-18, 24]. Behavioral insights
introduce the concept of behavioral motivation by means of i) individual behavioral
beliefs – leading to favorable or unfavorable habits towards the behaviour; ii) social
pressure and normative beliefs – influencing individual intention; and iii) control
beliefs, giving rise to perceived behavioral control with respect to the actual IEQ
control opportunities for the specific office configuration. As a rule, the more favorable
the individual habits and intention, the more encouraging the social pressure and norms,
and the greater the perceived control, the stronger should be the person’s motivation to
perform the behaviour in question [16].
In line with this work, outcomes from Shove [1] argue building occupants’
motivations, i.e. to adopt more energy conscious behaviors in offices, depends on the
diffusion of sustainable beliefs and actions through society. The study establishes that
users are generally not aware of their routines and habits, above all in energy field,
leading to overrated existing consumption patterns. Hence, Shove [1] concludes that
routine behaviors leading to consumption patterns are largely driven by social norms,
and are deeply molded by cultural and economic factors. However, the connection of
such correspondence remains controversial and quite undiscovered. Bridging this
causality gap is one of the scope of the proposed framework and questionnaire.
The starting-point of this work is that human behavior is stochastic by nature and
interactions among the several factors that influence occupant’s motivations towards
consumption practices are dynamic. Influencing factors change over time, rendering
individual consumer (occupant) behavior and the process of (energy) consumption
practices to some extent irrational, and therefore unpredictable. One of the main
conclusions curtailing from this research is that rather than focusing on individual
behaviors – and influencing factors – research should focus on the rise and alteration of
collective and social conventions shaped by geographical context, culture and norms,
driving occupant motivations, as they are crucial in fastening behavioral patterns, with
different consequences for building energy consumption and indoor environment
comfort. Further advancements of the presented study is the operative rollout of an
extensive survey questionnaire campaign in different geographical locations, among the
international research community embracing the IEA EBC Annex 66 on “Definition
and Simulation of Occupant Behavior in Buildings” [26]. The final aim of this study –
in a broader perspective – is to provide a standardized tool to drive effective occupant
behavior data collection, to enhance the state of the art on knowledge, methodologies
and tools.
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