Based on information from the Czech Statistical Office, Czechs spend on average 40.4 hours a week at work – and that is why it pays to think carefully about conditions we have in our offices and how to make sure that we feel comfortable there. That is the reason why Development News is bringing, in co-operation with the Czech Green Building Council, a specialist on healthy interior environment, a series about its individual aspects. These also include light climate, air quality, heat comfort, acoustics, ergonomics, active work environment, user comfort, transport access and location.
Daylight is an important factor
Based on the latest survey by the Association of Business Leaders and companies Skanska and JLL, some 87% of employees consider a sufficient amount of daylight in offices to be one of the key factors that improve their creativity at work. Maximizing daylight and optimizing the utilisation of artificial lighting should be a part of a comprehensive solution of contemporary healthy offices. The utilisation of modern technologies and LED lighting also brings about interesting energy savings. “Daylight is a natural feature, which significantly influences employees’ wellbeing and work performance. What also helps a well lit office is the right choice of lights, or – let us say – their radiating characteristics. Disturbing lighting must be prevented. Types preferred include those with diffusion radiation through microprism or indirect lighting components. This helps to achieve good light distribution within the office area, which consequently reduces eye strain from the contrast between work task and peripheral vision,” says Vladan Jesenský, Country Manager of Zumtobel Group, which belongs amongst the leading international producers and suppliers of comprehensive lighting solutions.
The intensity of artificial lighting in offices is set by a norm of 500 lx. Nevertheless, it is also necessary to work with other light aspects. An ideal light colour can be considered warm white ranging between 4,000 and 6,000 K. In order to provide individual comfort in a working environment, it is good to have the option of an extra light, for instance a table lamp, or to use a fluent light regulation. It is also important to focus on reflectance of the utilised materials in the office especially that of the desk top unit.
“The regulation of intensity of artificial lighting in an office belongs, depending on daylight, to other features that increase an employees’ comfort and also save considerably on electricity. Daylight changes its colour temperature within an approximate range of 3,000–8,000 K daily. In our latitudes, we mostly use lights with 4,000 K. In order to bring artificial lighting as close as possible to daylight, we can use lights that allow for a change of colour temperature. This changes in accordance with the time of the day and thus improves employees’ comfort as well as performance,“ Vladan Jesenský, adds.
Intelligent shading systems as a solution
Regarding daylight, the problem can mainly be in an even approach to it and its changing during the day. An even approach should be dealt with when designing the office, which should be open to daylight on more sides. The simplest way to work with its intensity is to use intelligent external and aesthetically suitable interior shading. These may be affixed facade components, window shutters, blinds, curtains or window foils. Shading features can allow different penetration, reflectance and/or an absorbance of sun rays. Another quoted parameter is the intensity of penetrating visible light of light transmission 380–780 nm. The colour of shading also has a significant influence on shading intensity.
Jan Polák, General Manager of Hunter Douglas, which produces and supplies shading technology, points out: “External shading (blinds, shutters and sun baffles) work best as a primary and effective barrier for heat penetration to the building and reduces the greenhouse effect. When combined with interior shading, the temperature of the interior environment is significantly reduced. It also eliminates the need for cooling in the rooms, which leads to a reduction in the consumption of non-renewable energy. Interior shading provides good visual conditions, controls the volume of light penetration and creates a pleasant contrast for eyes when optimizing daylight penetration to the interior.”
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