One staff member wants to make a telephone call, two others are chatting and the fourth needs to concentrate on solving a task – a daily challenge in thousands of offices. But how, in addition to noise levels, spatial factors such as temperature and light can be regulated such that employees feel well and healthy and are able to perform well? Researchers at the University of Stuttgart's Institute of Acoustics and Building Physics (IABP) are currently looking into this question, with the intention of coming up with a set of recommendations for how the office of tomorrow might look.
When humans first began to build shelters for themselves, they wanted to protect themselves from the elements, and, of course, to make life more comfortable for and increase the wellbeing of themselves and their families. “Starting about 100 years ago, building regulations have come to be dominated by the idea that a building ought to offer more than just protection from the elements”, as Professor Philip Leistner explains. He heads up both the IABP and the associated Fraunhofer Institute for Building Physics (IBP). The first building regulations published in the mid-20th century called for a minimum level of protection.
However, the insight that the conditions in spaces in which people spend time is of central importance in terms of their health, wellbeing and ability to perform was only recognized to a limited degree, whereby the ability to perform should not be understood in the sense that “for example, the objective is to squeeze every last drop of work out office workers”, the scientist emphasizes. Instead, they should find themselves in conditions in which they can perform their allotted tasks in a motivated, concentrated and efficient manner, so that they can enjoy their leisure time after an eight-hour working day “and”, according to Leistner, “eventually retire from working life in as healthy a condition as possible”.
Not just a matter of opinion
Up to now, buildings have been regarded as static or stationary, despite the fact that external and internal conditions are continuously changing. That is why the building physicists are working on one future-oriented topic in collaboration with numerous other institutes from the University of Stuttgart’s Collaborative Research Center 1244, “Adaptive Shells and Structures for the Built Environment of the Future”. “We're looking into the question of how a building façade would have to react to changing temperature, wind and noise conditions to ensure that the climate inside the building always remains comfortable”, says Leistner. The German Research Foundation is providing CRC 1244 with initial funding till 2021 worth ten million euro.
Yet the pivotal starting point for the IABP team involves a “communication task” as Leistner calls it: “If we want to design a space, we can’t ask people, ‘how many degrees Celsius do you prefer?’ or: ‘What Decibel level or what amount of CO2 would you like in the air?’”, he explains. “Yet, these are precisely the values that engineers have to plan for and configure”. That is why the building physicists are consulting with the users of the spaces whilst simultaneously measuring the physical parameters of the structures, both in laboratory experiments and directly in their working environment. A laboratory test might, for example, involve asking the test subjects to complete certain tasks whilst the room temperature is adjusted bit-by-bit. This enables the building physicists to determine the conditions under which the test subjects can best complete the tasks in question and feel most comfortable. This provides the planners with the precise values that they need. “Interestingly”, says the head of the institute, “the individual room parameters correlate to one another”. The test subjects experience a given constant noise differently under different temperature conditions.
The ideal office depends on the work carried out there
Whether or not and the extent to which an office is comfortable and conducive to good health depends on what goes on there. “The first thing we always ask is about the activity profile and work organization. We then correlate this information with the physical structural requirements and develop the workspace conditions that we need to aim for”, Leistner explains.
Starting about 100 years ago, building regulations have come to be dominated by the idea that a building ought to offer more than just protection from the elements
Prof. Philip Leistner, University of Stuttgart
Not luxury – just good economic sense
The building physicists usually encounter one of two different attitudes towards their results and recommendations. On the one hand, there is the works council whose primary concern is how a building's physical shortcomings impact the somatic and psychological wellbeing of the occupants. On the other side of the fence are the directors, who want the building physicists to explain how productivity or even turnover could be increased by investing in such things as air conditioning, acoustics or adjustable lighting. Leistner explains the potential benefits as follows: if we assume 60,000 euro per annum in personnel costs per staff member, then a performance dip of two per cent that could be prevented by modifying a building's physical properties, costs the company 1200 euro per capita per annum!“Although spending on building physics is a good investment, it often falls foul of budgetary rigor”, Leistner complains, citing the summer of 2018 as an example, which, he points out, demonstrated that heat-related performance dips and workplace absences cost significantly more than an air-conditioning system. “Many people are still having to deal with building environments that compromise rather than promote health, comfort and efficiency”, says Leistner: “Our research findings may well often seem like recommendations for luxury accommodation, but, actually, they are geared towards the mundane 90 per cent of our lives that we spend indoors”.
Daniel Völpel
Energy efficiency plus comfort factor
Creating a comfortable indoor climate as energy-efficiently as possible – that is also a central concern of the University of Stuttgart’s Institute of Building Energetics, Thermotechnology and Energy Storage (IGTE), which was formed on the 1st of July following the merger of the Institute of Building Energetics (IGE), the Institute of
Thermodynamics and Thermal Engineering (ITW) with its Research and Testing Centre for Thermal Solar Systems (TZS) and the Institute of Energy Storage (IES). Its research objectives include, among others, improving the energetic standards of buildings and plant engineering as a contribution towards lowering energy consumption and emissions, and to increase energy efficiency. The approximately 60 scientists also want to optimize the energetic function and indoor air quality of entire systems such as buildings and districts and contribute towards progress in the integration of renewable energies, especially solar thermal power, in heating, ventilation and air conditioning systems.