The environmental impact of a product depends on a variety of factors. In this paper, existing assessments are extended through the system dynamics methodology. A conceptual model was developed that contains several factors influencing on the use of washing machine and related CO2e-emissions. A stock and flow diagram allows for a streamlined environmental impact assessment of washing machines in households. The results show that both, wash frequency of households and the development of the energy consumption of washing machines are crucial factors for lowering future CO2e-emissions in the washing machines industry, whereas the sharing of washing machines did not show significant impact.