Procedure for planning artificial light
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and architects sometimes have divergent expectations. They hire consultants to help with the technical realisation of their ideas, to openly discuss them or to enhance existing designs with the use of light. The design process starts with an imaginary tour of the building. First of all lighting designers will, in their mind’s eye, record the daylight apertures and the directions of users’ views. Information on the building’s siting is collected, also on the orientation of windows, neighbouring buildings, vegetation and the time of use. These activities are part of the preliminary services and the outline proposal stage. The design concept is defined once the proposed function of a space is combined with a lighting idea. Most of the light we perceive is indirect light that is reflected onto the retina. The first step in the development of a design should be the assessment of the surface properties of the room. Its “furnishing” is also an important factor: a reading room has a certain type of light different from that of a hospital ward or a car museum. Light is specifically designed for different uses – even those within one room – taking into consideration the effect of colours and surfaces. In technical terms, this effect is measured as reflectance, a factor in the calculation of the necessary “light levels”. In this way the first mental sketch of the design evolves. Once the general idea of what areas need to be lit has been established, the rough positioning of the luminaires can be done and the luminaire types defined. The feasibility of these first ideas should be tested straight away. Proof of the expertise of a consultant lies in how far he is able to transpose a good design into a clear-cut system. If the design is feasible
in terms of ceilings, walls and floors, surface materials, cable runs, other aspects of M&E engineering, and apertures for windows and doors, then the necessary quantities of luminaires can be estimated and a rough calculation of the illuminance made. Generally, two to three different types of light will be employed, for example, vertical illumination, direct accent light and general illumination. The choice of luminaire depends on the type of lamp it operates. This interdependence arises from formal (aesthetic), technical and economic considerations. Finally, the circuits, including switches and alternative controls for the different system options, need to be defined. Emergency lighting is designed concurrently. Information on the types and quantities of luminaires, lamps and circuits, their installation and the required accessory devices is collected to produce a preliminary estimate of the proposal, and to work out its subsequent operating costs. Irrespective of this, as the project progresses, it becomes increasingly important to make sure the scheme is within budget – and of course fundamental to the success of the concept.
prior to approval. Amendments pose a problem for job profitability because it is generally expected that these are done at no additional cost to the client – and they can be time-consuming. Legal aspects of this problem are discussed in the section “The Lighting Designer’s Position from a Contractual Point of View” (see pp. 84ff).
A lighting designer who from the outset incorporates existing standards and regulations may also achieve good results. Generally, standards are recommendations, but in a commercial context and in conjunction with workplace directives, they are essentially binding. Other regulations, for example emergency lighting, must always be adhered to. The final proposal stage entails the coordination of architects and engineers, and the presentation of the design to the client which then needs to be approved. Often the user, architect or the client requests amendments to the scheme
2–4 Photographs and drawings of the cloud luminaire for the ceiling of the collection area, New Mercedes Benz Museum, Stuttgart (see p. 57ff) Architects: UN Studio van Berkel & Bos, Amsterdam Daylight design: Transsolar Energietechnik and ULRIKE BRANDI LICHT
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