BackgroundMaintenance and retrofitting of existing buildings and flats is of growing importance in the construction industry. In Austria, around 50% of the total annual investments are spent on renovation and refurbishment of old flats.However, in order to be successful these extensive refurbishment programmes are impossible without user integration - this is particularly true in cases that demand the legal consent of residents (e.g. additional energetical and ecological improvements). An early and systematic involvement of users could certainly help to avoid many of the problems and overcome the lack of support for extensive refurbishments that builders currently encounter. In our view, the demand for cooperative refurbishment is not only a function of necessity. User participation is rather seen as a chance for occupants to actively evaluate their own residential environment. Although a more active user participation may lead to additional organisational effort it is worth the attempt since in most cases this leads to a high acceptance and identification with the chosen solutions by the residents.Project Cooperative RefurbishmentThe Project Cooperative Refurbishment studies the needs of occupants during refurbishment processes in multi floor buildings, develops efficient and feasible models of user participation and implements exemplary participation processes in refurbishment projects.The most important steps in the project are:* problem evaluation from the building owners' point of view* problem evaluation from the occupants' point of view* evaluation of various international models for participation in refurbishment processes - selection of particularly promising methods* development of a participatory model for user involvement in refurbishment processes* implementation of two pilot projects as best practice examples.The project develops a model of participation outlining an ideal process integrating occupants (and possibly also neighbours), designing a modular system that can be adapted to specific practice situations, involving users during the whole process of refurbishment, considering and promoting normative aspects of sustainable use of accommodation and making suggestions for the integration of neighbourhood concerns and local politics.This flexible and modular model of participation can be implemented in refurbishment processes for old buildings. A practice brochure will document the results and provide guidelines for construction companies on how to implement the model.The research project will be finished in July 2004. At present time interviews with experts in the field of refurbishment and participation are done, focus groups and discussions with occupants who were involved in former refurbishment processes are in preparation. Best practice models in Austria and Europe are analysed. In addition, housing associations have been contacted for possible pilot projects and one has already started.The presented paper will describe the most important steps and results of the research project. We will outline the needs of occupants during refurbishment processes in multi floor buildings with a special focus on ecological improvements. Furthermore we will discuss efficient and feasible models of user participation and we will present some current experience related to the implementation of such participation processes in refurbishment projects.