Occupant Satisfaction In Buildings Research Articles

Introducing the concept of acoustic personalised environmental control systems (Acoustic PECS) within the framework of IEA EBC Annex 87

The availability of systems that can locally adjust environmental parameters holds the potential to enhance building occupant satisfaction by considering individual sensitivities, expectations, and needs. To this aim, Personalised Environmental Control Systems (PECS) are being studied as solutions that can provide individually controlled environments in the immediate surroundings of an occupant, without affecting directly the entire space and other occupants' environment. The concept has been primarily developed to address individual control of the thermal environment and perceived air quality, as in chairs with heating/cooling functions and desks equipped with personalized ventilation systems. By extending the concept of PECS to the acoustic domain, a framework on Acoustic PECS is here introduced and exemplified. The study builds on ongoing research within the IEA EBC - Annex 87, dedicated to investigating the Energy and Indoor Environmental Quality Performance of Personalised Environmental Control Systems.

Can occupant voting systems provide energy savings and improved occupant satisfaction in buildings?—a review

Occupant voting system(s) (OVS) are digital tools used to collect continuous and real-time feedback on occupants’ perception of and desired changes to the indoor environmental quality. Occupant feedback acquired with OVS is typically used together with indoor environmental measurements for room temperature control. Additionally, OVS has been used to collect occupant satisfaction data for post-occupancy evaluation and complaint data used in fault detection and diagnostic of building operation. The present paper presents a review of sixty scientific publications on research studies using tools denoted as OVS. The review identified a median energy saving of 22% and a median improvement in occupant satisfaction of 34% for the reviewed OVS studies. Across the reviewed studies, a single occupant voted on average one vote per day. The review suggests that the studies using OVS interfaces that were easier to use by the occupants, such as wearable devices, obtained a higher voting frequency than OVS interfaces accessed via websites. Moreover, the review identified that the study design, such as the duration and number of participants or whether energy savings were estimated using simulation or measurement, affected the voting frequency and the obtained energy savings.

An indoor air quality and thermal comfort appraisal in a retrofitted university building via low-cost smart sensor

Occupant health can be strongly influenced by indoor air quality due to time spent indoors (90%). Such quality can be impacted by indoor atmospheric pollutants present. Therefore, demand-controlled ventilation can be a key to improving indoor air quality. The main aim herein is to scrutinize measurement results of several air pollutants possibly existing inside university building including CO2, volatile organic compounds, formaldehyde, benzene, CO, PM2.5 during three measurement campaigns (March 2017, May 2017 and October–November 2017) via a smart sensor specially developed. Likewise, some factors to assess comfort such as relative humidity and ambient air temperature were examined. CO2 were found to be higher during periods of occupancy with concentrations exceeding 2000 ppm during the first campaign. As a result, the occupants felt uncomfortable. Analysis of the survey results regarding the indoor air temperature showed that 80% of occupants found the temperature during school periods to be uncomfortable. In addition, the ICONE air containment index was extremely high, indicating that the deemed class was confined during occupancy. The outcomes will be useful for the development of future indoor air quality guidelines, ventilation design and occupant satisfaction in buildings.

Green Building Occupant Satisfaction: Evidence from the Australian Higher Education Sector

Universities spend billions of dollars on green buildings as a sustainability commitment. This research investigates occupant satisfaction with indoor environmental quality (IEQ), building design (BD), and facilities management (FM) in five highly ranked green higher educational buildings in the subtropical climate of Australia, in comparison to nine non-green counterparts. The results disclose that the green building users were more consistently satisfied than the non-green building users with BD&FM elements, such as design, needs from facilities, building image, cleaning, the availability of meeting rooms, and storage. On the other hand, the study revealed weaknesses of green buildings in IEQ, such as noise, ventilation, and artificial lighting. The individual environmental control positively correlated with satisfaction in non-green buildings, but did not significantly affect satisfaction in green buildings. This study also identified the influences of non-environmental factors on occupant satisfaction, such as gender, age, sitting close to a window, hours spent in the building and in the workstation, and the number of people sharing office space. The research provides evidence and guidance for investing in, designing, and managing green educational facilities.

Energy consequences of Comfort-driven temperature setpoints in office buildings

The diversity in occupants’ thermal comfort preferences is usually overlooked in the operations of centralized-HVAC buildings and room temperatures are maintained within a narrow temperature range. In this study, we first created total of 400 comfort profiles for four major climate zones and for two seasons (winter and summer), using the RP884 database. We then systematically simulated and quantified the impact of using zone level setpoints (based on the generated comfort profiles) on energy consumption in office buildings. We also evaluated the consequences of using comfort-driven zone level setpoints on occupant satisfaction. The results indicate that using comfort-driven zone level setpoints can lead to an average increase in occupant satisfaction of 25% compared to the fixed building level setpoint of 22.5 °C, and 40% increase in occupant satisfaction compared to the DOE reference cooling setpoint of 24 °C and heating setpoint of 21 °C. Using comfort-driven zone level setpoints can also lead to average energy savings of 2.1% when compared to the fixed building level setpoint of 22.5 °C or average increase in energy consumption of 6.2% when compared to DOE reference setpoints, depending on the building size, construction and climate type. The variation in energy consumption caused by diverse occupant preferences is less than 2% of the annual building energy consumption. Furthermore, we demonstrated that even with the zone level setpoints, it is quite difficult to meet the ASHRAE requirement of 80% occupant satisfaction, which supports the use of personalized comfort systems to improve occupant satisfaction in buildings.

Comfort signatures: How long-term studies of occupant satisfaction in office buildings reveal on-going performance

Occupant surveys reveal how people in buildings perceive their internal environments. The Soft Landings extended handover process, which requires project teams to focus more on operational outcomes, has led to the use of occupant surveys during a three year Soft Landings aftercare period to provide a means of checking whether the desired outcomes have been met. However, little is known of the longitudinal perceptions of occupant satisfaction in buildings, and the relationships between those perceptions and the many environmental, seasonal and functional comfort variables that act upon occupant satisfaction. This paper reports the results of time-series surveys on two office buildings. Occupant satisfaction scores have been compared with the technical, organisational and functional contexts in the work environments, such as density, workgroup sizes, and cellular and open-plan layouts, to determine whether changes in these parameters have significantly altered levels of perceived occupant comfort and productivity. The research found stability in some contexts but statistical declines in others. Conclusions are made regarding the key operational factors that may contribute to changes in occupant satisfaction over time. Factors that might constitute limits to office carrying capacity are discussed. Practical application: The growing use of the Soft Landings approach to building procurement and handover, with greater emphasis on designing for improved operational outcomes, is creating a demand to understand more about occupant needs and expectations. The central government equivalent – Government Soft Landings – is similarly placing a requirement on public sector construction projects to deliver buildings with improved environmental and functional outcomes. Delivering these expectations requires construction professionals to develop skills in building performance evaluation, particularly in understanding the primary drivers that lead to high occupant perceptions of comfort, health, productivity and wellbeing. This research provides real-world evidence to clients and their design advisors on the key factors for ensuring long-term occupant satisfaction, while for building management professionals the research identifies some organisational risk factors that may lead to a fall in satisfaction during long-term operation.

A Study of Thermal Comfort and Occupant Satisfaction in Office Room

This paper presents an investigation regarding the effect of indoor thermal to building's occupant satisfaction which is equipped by mechanically ventilated. The investigation is consisted of two parts, in which the first part is to visualise the indoor environmental quality of the office room in-term of air velocity distribution and indoor temperature distribution. Whereas, the second part is to obtain the perception of building's occupants regarding their satisfaction to the indoor air and thermal inside the building. An approach of modelling and simulation was carried out using COMSOL Multiphysics software to visualise indoor environmental quality and an approach of questionnaire was adopted to obtain the perception of building's occupants. The results show that the geometry model also affects to the air circulation and maintain indoor temperature distribution. This evidence occurred when the distribution of indoor air of office room didn’t distributed homogeneously to the hallway as impact of the streamline, but the distribution of indoor temperature is still uniform. Additionally, the condition of temperature inside office room is not a single factor that contribute to the dissatisfaction of building's occupants. Since most of office workers are unauthorized to adjust temperature and air velocity of the air-conditioning system, this contributes to 40% of respondents that are dissatisfaction with temperature and air velocity. Finally, this study found that the relationship amongst indoor environmental quality to produce occupant satisfaction is a complex system that need to be assessed comprehensively. Besides, it is invaluable to advance our understanding of the relationship amongst ventilation system, occupant behaviour, and building energy in tropical climate in assessment of occupant satisfaction.

On a Post-occupancy Evaluation Study of Effects of Occupant Behavior on Indoor Environment Quality in College Buildings in Chongqing

Some field studies of the effect of college buildings environment parameters on environmental and study satisfaction were conducted in Chongqing of China. A post-occupancy evaluation (POE) approach was used to analyze the survey results of building occupant satisfaction and the measured indoor environment quality. Occupants completed a questionnaire related to environmental satisfaction. Meanwhile, a long-term objective measurement was proceeding to characterize the immediate environment experienced by the occupants. This study analyzed the subjective and objective measurements of indoor environment quality (IEQ) from four parts: thermal environment, indoor air quality (CO2), visual and acoustic environment. The data collection for these studies was based on full consideration of user’s energy consumption habits and environmental control behavior in using HVACs. This offered the opportunity to compare the study results at the user side demand level, with the goal of identifying parameters consistent in affecting occupant satisfaction.

Spatial mapping of occupant satisfaction and indoor environment quality in a LEED platinum campus building

This paper reports a post-occupancy evaluation study of a LEED Platinum building on a university campus. A multiple-tool POE approach with GIS-based spatial mapping method was used to analyze and visualize the survey results of building occupant satisfaction and the measured indoor environment quality.The occupants were overall satisfied with the indoor environment in their workspaces in the building of study, though thermal comfort was comparatively low with high percentage of occupants reporting their workspaces too cold. Air movement was found to be lower than preferred by the occupants, especially in interior offices where CO2 level was also predominantly higher. Light levels in the building were found higher than preferred. Electric lighting power density installed did not reflect the fact that daylight is available for most of the lab and office spaces. Satisfaction with speech privacy was found lower in individual offices related to the construction detail of the connection between curtain wall and interior walls.Linking performance outcomes with spatial information improves POE data management. Spatial mapping allows reasons that cause occupant discomfort and dissatisfactory measured performance to be identified more intuitively and makes it potentially easier to communicate POE results with architects, engineers and facility management professionals, in order to engage them in the collaborative effort of continuous building performance improvement.

Are ‘class A’ temperature requirements realistic or desirable?

It requires more energy to maintain a narrow indoor temperature range than a broader range, in which the building may be allowed to float with reduced conditioning for longer periods of time. A narrow range should presumably be preferable to the building occupants to justify its increased energy cost. At what widths are temperature ranges detected, preferred, or judged unacceptable? Three databases of occupant satisfaction in buildings are used to examine the acceptability of three classes of temperature range currently employed in the ISO and European standards, and proposed for the ASHRAE standard. These are alternatively identified as class A, B, and C, or category I, II, and III, but their specifications are identical. The A class (I category) is found to confer no relative satisfaction benefit to individuals or to realistic building occupancies. In addition, the differences in B and C class satisfaction are small.

INTELLIGENT FACADES: OCCUPANT CONTROL AND SATISFACTION

This paper, through the discussion of recently completed doctoral research, addresses the influence of occupant control in achieving occupant satisfaction in buildings with intelligent facades. The focus of the study is the most common form of intelligent facade which the research has termed automated glazed facades. These are defined by this research as highly glazed facades capable of independent physical reaction to either external or internal conditions or presets. The findings of a series of occupant satisfaction surveys and interviews in automated glazed facade buildings in the UK, Germany, Switzerland, France and the USA are discussed Occupant control is found to be the dominant issue affecting occupant satisfaction in buildings with intelligent facades. The importance of occupant control is shown to be rooted in the occupants ability to achieve their desired conditions. The main elements of occupant concern are identified and the potential of the automated provision of occupant requirements is discussed in light of the findings.