paper ID: 337/p.1 Traffic noise control by canyonisation of roads E.Ph.J. de Ruiter Delft University of Technology, Faculty of Architecture, Dept. Building Technology, Environmental Design, Delft, The Netherlands, E.Ph.J.deRuiter@bk.tudelft.nl Peutz Consulting Engineers, Zoetermeer, The Netherlands, zoetermeer@peutz.nl Sound transmission from roads to the environment can be reduced by creating “urban canyons”: continuous shielding buildings bordering the roads. Noise shielding is a complex phenomenon. The applicable calculation models require detailed information including the flow of traffic, average velocities, pavement type, positions of all objects etc. In early stages of design however, this information is usually not available. Yet in these stages the possibilities of realising efficient land use must be explored. Therefore, a different approach was chosen. Starting points are the cross section of a simple street canyon, and the goal of creating a liveable lee area (“hinterland”), i.c. noise load 50 dB(A). The main variables describing the situation are the height of the buildings and the position of the residences in the lee area. In urban planning, it would be useful to get an indication of the feasibility of this concept. If standard values are chosen for the other variables, the admissible daily traffic flow can be determined. In general it is possible to judge whether the resulting number is within limits of feasibility. 1. INTRODUCTION Sustainable building is part of sustainable development, “ that meets the needs of the present generation without compromising the ability of future generations to meet their own needs” (Brundtland, [1]). It demands consciousness of the limited resources of the earth, and its limited capacity to cope with pollution. Among many other things, this implies efficient land use in cities, and elsewhere. Zones along main roads in cities with high noise impact have been used only for low-grade buildings, because of practical or legal reasons. Although being an effective means of noise control, this must be considered now as a waste of land, we can no longer afford. Bordering these roads with continuous apartment buildings (‘ canyonisation ’) is proposed as a way to reclaim these zones. The buildings provide noise reduction to the areas in the ‘backyard’ in the first place. In this way they protect land from excessive noise loads. Secondly they offer housing capacity themselves. Research was aimed at the development of tools to stimulate this approach. From the experience that acoustical aspects can play an important role, but are often neglected -presumably for lack of available methods in the conceptual design phase- the focus was set to acoustical tools. The design process related to canyons embraces the following acoustically important questions. a) How to achieve the required shielding? b) Which special properties of the first-line buildings are required? c) What is the influence of the termination of the first-line buildings? d) What is the influence of apertures for passageways through a first-line building? Several tools have been developed to facilitate the process, and answer the questions above: