This research intended to understand the effect of renovation solutions on occupants’ behaviour, and the effects of the behaviour on the indoor environmental quality of the buildings. The investigation is based on the findings from a short, in-depth monitoring campaign in four apartments in the Netherlands. The results showed that the households studied have different preferences for comfort, as well as ways to interact with the building. The small range of options provided by the systems created some level of dissatisfaction in three out of the four households studied regarding temperature (control), air quality, or noise produced by mechanical ventilation system. The monitoring results confirmed that the apartments were within a good range of thermal comfort, however the residents complained about lack of control over the indoor environment. Furthermore, high CO₂ levels were found in three of the four apartments, especially at night. In these homes, the residents kept the ventilation setting on the lowest due to the noise produced by it, or due to lack of knowledge on the functioning of the system. In addition to the lack of control and lack of knowledge, the residents reported a lack of feedback from the Heating Ventilation and Air Conditioning systems to know whether they are working correctly. These results emphasize the need of user-centric design, and the need for people to be able to control their environment. Systems design should consider the actual needs and preferences of the occupants, while interfaces should be designed to provide timely and accurate feedback to the user.

This paper innovates in the relationship between sustainable technology suppliers and users, using the example of heat pumps. Heat pumps are necessary for energy transitions in Europe. However, in everyday life in households, heat pumps are often not used as the technology developers intended. This discrepancy presents a challenge for heat pump supply-side actors such as manufacturers and resellers. This paper first presents a design perspective on user improvisation and highlights its value for innovation. We synthesized the perspective in a sensitizing video. We then employed this video to engage with nine supply-side professionals in the Dutch heat pump value network and conducted semi-structured interviews with them to understand their responses to improvisation. We categorized their responses and identified the factors influencing the choice of response. We identify ten different responses and nine motivating factors. We then interpret the responses in the light of our design perspective on user improvisation to highlight areas for socio-technical innovation in the relationship between the heat pump supply and use sides. This innovation can support heat pump uptake and satisfaction and thus improve the quality and rate of renovations.

In this paper, we develop a comprehensive behaviour model for residential buildings that considers the diversity among households. While existing behavioural theories from social and psychological sciences have been used in building research, they often lack technical detail, contextual aspects, and focus primarily on behavioural change. The authors propose an interdisciplinary theoretical model that integrates insights from behavioural science and engineering dimensions. This model aims to link measurable drivers directly to energy outcomes, consider building-related contexts, and reflect the complexity of high-performance buildings. The research consisted of the quantitative analysis of building monitoring data and the analysis of interviews using thematic analysis. The mix-methods approach allowed to obtain new insights into the relationship between the aspects that affect occupants' behaviour. An interdisciplinary model is developed based on the results from the analysis, existing theoretical models used in building research, and previous studies on occupants' behaviour. The model is intended to support the identification of occupants' behaviour drivers, inform user-centric and energy-efficient building design, enhance decision-making for building monitoring and simulations, and aid in various practical applications such as performance assessment and energy contracting.

Domestic heating systems need to change to meet climate targets. We draw on practice theoretical concepts to understand what is needed to integrate heat pumps in Dutch households. From a design orientation, we view households as creative actors integrating technologies into daily life. We report on an ethnographic study of the disruptions and resulting reconfigurations that occur when heat pumps are introduced in Dutch households. Our findings reveal a variety of practice reconfigurations around heat pumps. We also find that these reconfigurations are related to and may influence other practices, including professional practices. We discuss our findings in relation to policy, technology development, and design, and conclude that the required reconfigurations in Dutch household practices could be supported, and that innovative practice reconfigurations emerging from internal household dynamics could contribute to sustainability transitions.

By 2027 more than 530 M homes will likely adopt at least one type of automated system. This means that a growing number of residents will be living with automated technology in the home, everyday. But living with smart homes is full of conflicts between what residents find appropriate and what technology does instead. Previous research, centering end-user needs, has often focused on smooth living experiences through graphical user interfaces and improved predictions. In this research, we take the more-than-human lens of co-performance to put crises in everyday practices in view, and to conceptualize a new notion of interface. Based on ethnographic data from 11 households, our findings illustrate how crises reveal conflicting ideas of appropriateness, how residents reconfigure their co-performances with technology in response to everyday crises, and how new interfaces are enacted as a result. We conclude by illuminating how researchers and designers should not look at the conflicts and crises emerging in the more-than-human home as something of which to get rid. Instead, they are opportunities for residents and buildings to respond to one another in the context of everyday life and to enact interfaces that were not pre-designed into the building.

Dwellings and systems are becoming ever more complex. In achieving high energy performances, the interaction among user, building and systems plays an increasingly crucial role. We studied this interaction in 16 recently renovated low-energy dwellings, to advance the field in terms of methods, and to derive pointers for improved renovation concepts. We used sensors to monitor the indoor environment. And we further developed a method that uses questionnaires, diaries and a so-called 'walk through the house' interview technique to gain insights into occupant behaviour and the reasons for the occupants' behaviours. The results show that the observed behaviour was almost always a normal response to the situation, but often not the behaviour that was expected when designing the renovation concept. A major reason for this was the occupants' efforts to reduce discomfort, which was often the result of the renovation solution itself (for example draught, noise or a warm bedroom). So, we found that behaviour was often a quite normal reaction to the renovation solution. We conclude that the resulting underperformances of renovation concepts are caused by technology centred design. We posit that this can be improved by testing renovation concepts in real world situations.

As the goal-setting in the European Green Deal is to reach carbon neutrality by 2050, great efforts have been put to improve the energy efficiency in residential buildings. As residential buildings are towards high energy efficiency, building envelopes are becoming better thermally insulated and systems are becoming more energy-efficient. Therefore, the role of occupants in the actual building performance is becoming more important. However, contradictions exist between the uncertainties caused by occupant behaviour (OB) and the over-simplified consideration of OB in building design. Therefore, this paper aims to present a state-of-the-art of how OB is represented in residential buildings. Through a literature study, this paper first reviews different occupant behaviours and how they are considered in the design and operation of high-performance residential buildings. Modelling methods are categorized by occupant activities. In addition, behavioural theories in the application of analysing building performance are reviewed. How the behavioural theories are integrated with state-of-the-art building technologies is outlined. Finally, challenges and suggestions for representing the interaction between occupants and buildings in the design and operation of residential buildings are discussed.

Renovation projects in social housing tend to focus on diminishing the costs of the renovation. An affordable solution is sought for an average household, thus assumptions are made about the residents' behaviour when calculating the energy performance of the dwellings. However, households have different needs and preferences, and therefore the actual use of the building can affect the achievement of the zero energy goals. In the Netherlands, until 2020, the calculation of the energy performance coefficient (EPC) was necessary to obtain building permission. The EPC was calculated based on standardised occupancy, and took into account the characteristics of the building envelope and installations. Furthermore, the EPV (energieprestatievergoeding, energy performance compensation in English) is an instrument used by housing associations and landlords to recover part of their investments in renovating social housing into (nearly) zero energy homes through a regulated increase in the rent, while protecting the residents from increase on their costs of living. In this research, we used a monitoring case study in the Netherlands to investigate the effect of assumptions made during design regarding occupants' behaviour, preferences, needs and lifestyle on achieving energy neutrality goals. The following questions are answered: What assumptions where made during the design of the building, and how do they differ from actual behaviour?, and what are the consequences of the behaviour for the performance of the building and for the EPV? The objective of this research is to determine the importance of design assumptions in the design and evaluation of zero energy buildings.

This study aims to collect data on the activities, postures, dis(comfort), and needs of train passengers. Observations in the trains and questionnaires completed by train passengers were used. The online questionnaire was completed using the smartphone of the passengers during the train trip. The most often observed activity of the passengers was using a smartphone while travelling. They used a smartphone to listen to music, chat or type, look at a video or picture, and to read. Most passengers reported that they hold a smartphone with both hands and used a smartphone with the right hand also. The thigh support and the armrests of the seat showed the lowest comfort and certainly have room for improvement. Future research could be considered to design the seat to increase passenger comfort while using a smartphone.

BACKGROUND: The number of smartphone users is immense. People can do ever more with a smartphone. Smartphones are used everywhere, including in bed and on the sofa. The awkward postures taken in these situations affect comfort and discomfort. In designing a bed, it might be useful to know which position is comfortable for smartphone use on a bed. OBJECTIVE: The objective was to define the most comfortable trunk angle for smartphone use on a bed. METHODS: To study comfort and discomfort, 52 participants were asked to use the smartphone on a bed. The trunk angle of this bed was adjusted to 6 positions from flat to upright and for each angle the comfort and discomfort was recorded. RESULTS: The results showed that the participants prefer a trunk angle range around 120 and 142 degrees. At the best trunk angle 29% of the participants felt comfort in the legs, 25% in the upper back and 16% in the shoulders. However, in this position 36% also mentioned discomfort in the lower back and 24 % in the neck. CONCLUSIONS: For smartphone use a bed is preferable which enables a trunk angle of around 120-140 degrees. For the legs this is comfortable. However, for the neck and upper back the problem of discomfort still needs attention.