The proposed housing unit aspires to enhance the collaboration between local population and construction experts and also to combine strong and light structures in order to respond to fast and sustainable construction. We choose to focus our research on Turkey, and more precisely on the housing settlements “gecekundu” of Istanbul. The “gecekundu” housing is constructed overnight : concrete, timber and disused material serve the needs of fast construction. We aim to improve the housing conditions of such populations, by supplying them with knowledge and also letting them build the house on their own along with the help of experts. [DESIGN] The design of this urban housing unit is based on a concrete core and a light wooden structure that is attached and supported by it. The concrete core is a prefabricated box that accommodates the kitchen and the bathroom, which are the basic utilities that we would like to be accessible to every house. This box is supplied by a local construction unit : in this way the local economy is developed too. There is also the possibility for this unit to have a rainwater gathering unit in order to provide an autonomy to the housing. This unit serves as a primary element around which the house is constructed: the proposed structure is wooden, light, simple and can be realized by a non- expert, in this case, the families living in these houses. The living room and two bedrooms, one for the parents and one for the children are thus constructed around the main unit. The structure is elevated from the ground floor in order to prevent problems of humidity, insects and mould. The external dimensions are 15 x 7.20 m and the surface without the porch is 100 m2 [IN SITE COLLABORATION] The prefabricated core unit is supplied by a manufacturer. During the installation, the collaboration of experts and the local population is important. People participate in building their own home, as they already used to do in Istanbul, but the advice and the guidance on behalf of the experts help them learn and understand the materials and the procedure in a thorough way. [NATURAL DISASTER RESPONSE] This housing unit is designed to resist to natural phenomenons. The concrete unit provides shelter for the entire family during extreme conditions such as earthquakes or hurricanes. In the extreme case where the light structure does not survive the hazard, this unit serves as the core for reconstruction : the house is reconstructed again very fast. Additionaly, since the housing unit is elevated from the ground, it can resist up to a certain level of floods.