the life cycle performance of sustainable renovation concepts

in time, due to changed insights. The environmental impact categories that are takeninto account by a LCEI evaluation are:• Greenhouse gasses• Ozone layer• Acidification• Eutrophication• Heavy metals• Carcinogens• Pesticides• Summer smog• Winter smog• Energy resources• Solid wasteAt the evaluation of the LCEI, a weight factor has to be assigned to each impactcategory, which makes it possible to connect with the actual interpretation on impactcategories at all times.The LCEI is identified as a factor of influence as a result of the evaluation of the existingsustainability assessment tools- GPR Gebouw- GreencalcBesides that, the LCEI is mentioned as a factor of influence on the performance ofrenovation concepts at two expert interviews. The experts that mentioned the LCEI as afactor of influence are listed in appendix B. Also, the executed literature study points outthat the execution of a life cycle assessment of a product provides the most comprisingview on the environmental impact of the product, and therefore is an important factor ofinfluence on the performance of sustainable renovation concepts. Lastly, the sub-factorsthat determine the LCEI are confirmed in the model testing phase.LIFE CYCLE COSTSThe life cycle costs (LCC) are costs that result from the application of a renovationconcept, the energy and maintenance costs during the life cycle of a building, and thedisposal costs at the end of life of a building.The LCC factor is integrated in the model because:- Large scale housing renovation is only realized if it is financial feasible.Companies as real estate developers, real estate investors, and housing corporationsmainly focus on the financial feasibility of projects. These parties have the capacityand competences to execute large scale housing renovations. However, they will onlyexecute a renovation project if they are convinced about the attractiveness on thefinancial aspect. In other words, the sustainability aspect is inferior to the financialaspect in most cases. This situation also accounts for individual house owners.As a result of the motivation above, the financial aspect has to be integrated in themodel. None of the current existing tools integrates the financial aspects in thesustainable performance evaluation.The LCC is mentioned as a factor of influence on the performance of renovation conceptsat five expert interviews. The experts that mentioned the LCC as a factor of influence arelisted in appendix B.Besides that, the executed literature study resulted in the identification of the LCC as animportant factor of influence on the sustainable performance of products. In severalscientific articles, the principle of eco-efficiency is introduced. This principle refers to theintegration of financial aspects to the life cycle assessment of products. The exclusion of50