|M.Sc Student||Bshara Rezik|
|Subject||LightBIM - A Building Interior Lighting Analysis and|
Evaluation Model - A Qualitative and Quantitative
|Department||Department of Architecture and Town Planning||Supervisor||Dr. Yezioro Abraham|
|Full Thesis text|
For a design to be functional, safe, comfortable and pleasant, the designers should consider multiple performance aspects: space size, building materials and textures, colors, openings’ sizes, comfort conditions, acoustics, thermal qualities, aesthetics and lighting conditions.
Evaluating some of these aspects requires simulations in order to collect the information necessary for the design process' decision-making. The earlier simulations are made, the lower is the effort needed for design changes to be made. This research creates a BIM based comprehensive performance driven design process, with focus on natural daylighting conditions.
The prediction of a building’s performance under daylight is possible and can be performed through many physical and computer based tools available that can measure amounts of light hitting the building’s surfaces and the shape and nature of the shadows it casts onto its environment and itself. They can also measure, calculate and display qualities of light that affect the building’s user’s well-being and visual comfort, thus creating an overall assessment of a building’s natural (and artificial) lighting performance.
Evaluating a building’s lighting conditions during the design process can be a complicated task, hence usually not performed at all or, at best, left for late stages in the design process, performed by specialists and lighting consultants. This is, in part, due to the fact that most architects work in 2D CAD environments, lacking the information necessary for lighting simulations, and to the lack of knowledge and experience in the field.
Working in BIM environments, architects and engineers are able to continuously revise and examine their design under one comprehensive model that contains all the building’s information. Most existing lighting simulation tools have yet taken advantage of BIM, and those that do are intended for developed stages of the design. This research, therefore, suggests a model that is an integral part of the BIM environment, working as a seamless part of the design process starting from the early stage of design.
The proposed model, LightBIM, allows the examination of the design's interior daylight conditions by means of illuminance, luminance, glare probability and adequacy to standards like LEED, SII 8995 and SII 5281, thus providing an overall, quantitative and qualitative, evaluation of interior daylighting conditions. It connects Revit with Radiance, a validated lighting simulation engine, and creates a seamless design and evaluation process.
The model is easy to use, transparent and educational. While the designers have to make few decisions before the simulation starts, it immediately exposes them to the visual and quantitative meaning of their decisions, giving them a deeper understanding to the simulation process and its results. The model allows the designer to examine various design options during any stage of the design process and provides a comprehensive view over lighting qualities, making it easier to understand the effect design decisions have over daylighting conditions in the space.
The model was tested on a case study demonstrating a complete design process of a small design gallery building, showing the way that the model affects the process and the decisions made throughout it.