PLEA2006 - The 23 rd Conference on Passive and Low Energy Architecture, Geneva, Switzerland, 6-8 September 2006 Housing Daylight in Urban Centres. Study Case: Havana Dania Gonzalez Couret, Anielsys Zorrilla and Hector Gomez Faculty of Architecture, ISPJAE, Havana ABSTRACT: The integral rehabilitation of central urban areas is a main condition for sustainability, allowing the preservation of the heritage and taking advantage of the urban land as well as the existing facilities and infrastructure in the city centre. Urban microclimate has been recently studied and some contradiction in the appropriate architectural designs to solve different climatic variables, arise from these researches. The present paper offers the results of the indoor daylight simulation in some architectural models proposed to be inserted in the traditional centre of Havana. From these results, some recommendations and indexes for architectural and urban design are proposed in order to guarantee appropriate indoor daylight in the new multifamily buildings to be built in those central urban areas in Havana. Keywords: housing daylight simulation 1. INTRODUCTION The integral rehabilitation of central urban areas is a main condition for sustainability, allowing the preservation of the heritage and taking advantage of the urban land as well as the existing facilities and infrastructure in the city centre. Urban microclimate has been recently studied and some contradictions in the appropriate architectural designs to solve different climatic variables arise from these researches. However, daylight seems to be the more precise variable to set the limits between the land occupation index and the indoor environment. The present paper offers the results of the indoor daylight simulation in some architectural models proposed to be inserted in the traditional centre of Havana. 2. CENTRAL URBAN AREAS Figure 1: View of Havana Centre. Traditional central urban areas are usually preferred by people, because of their environment; level of services, facilities and animation; centrality, communication and transportation, and also, because of their historical and cultural accumulated values. Those are important reasons for their preservation. These urban zones are generally high density and compact in land occupancy (index higher than 0.8), with continues façade lines, common walls without spaces between buildings in long and narrow plots, organized in blocks according to a grid derived from the original Mediterranean urban model brought to America by the Spanish colonizers. Then, needed relationship between indoors and outdoors in buildings (for daylight, ventilation and sights), are produced to the street (limited by the narrow plot) and to an internal yard, which has suffered an evolution from the original court yard to the more common and traditional lateral yard, arriving to the small yards called “patinejos” or “wind boxes” in the multifamily buildings constructed in the 50’s as a result of the land speculation. 3. URBAN MICROCLIMATE In spite than the architectural model proposed in almost all bioclimatic manuals for warm and humid climates suggests an open urban solution, studies carried out 20 years ago in Havana showed that these compact urban areas could be better than the modern open ones according to thermal environment [1]. The explanation of this phenomena suggested a different microclimatic behaviour of the compact urban areas based on the thermal inertia, according to what, ventilation could be no so important as in open urban models it was. However, there have been