The paper discusses the role of trans-disciplinary research networks tackling the challenges of sustainablerenovation such as; environmental impact of substitute building materials and waste, relocation of tenants, lackof skilled labor, rent increase due to high renovation costs, and provides a detailed perspective on the effects interms of both new forms of collaboration and research results obtained by the researchers and practitionerswithin the network. The research network Sustainable Integrated Renovation SIRen has become a platform forresearchers and actors such as building owners, housing companies, facility managers, contractors, consultants,architects, building conservationists, authorities and tenants’ organisations to meet and work together ontechnical, environmental, economic, social and cultural historical aspects on renovation of buildings, as well asto identify and discuss new challenges. A multi-aspect process covering all aspects that must be considered bythe various actors during different stages of the renovation process has been developed and implemented in four‘Living Labs’ in real renovation projects. This involved using new modes of work in early stages to place thefocus on sustainability aspects and work on new dialogue methods and using methods to evaluate the variousrenovation options based on technical, environmental, economic, social and cultural historical perspectives.