The aim of this thesis was to examine the impact of the living environment to people’s wellbeing and mental health and how to utilize the results in different types of therapeutic environments for mental health clients. The purpose was to design and decorate a common lounge in a private residential home for mental health clients -based on the needs of the residents. The residents were involved in the design process by means of a group interview. The results were used when making the final decisions about the interior decoration.

The design process was based on background theory on environmental psychology, interior design, colour therapy and the effect of colours on wellbeing. The theory was adapted to source literature on mental health disorders and observations on schizophrenia. The thesis was commissioned by Imatran palvelukoti Oy, a private housing service provider in Imatra and the decoration was executed in a housing unit Valionpuisto in January 2011. Mäntylä, the actual building where the decoration was executed, is a home for longterm residents suffering from schizophrenia. In this study the research methods used were participant observation, individual and group interview.

The thesis resulted in the decoration of the common lounge in Mäntylä. The thesis includes argumentation of the choices made and the decorated space is also documented. According to the research results, adequate and intentional interior design has a positive effect on the well-being of people recovering from mental health problems. With properly executed decoration it is possible to promote social interaction, to activate residents to develop themselves, to create experiences, and to provide the residents with a space where they can calm down and relax.

Further development idea is to utilize the possibilities and benefits of well-planned interior design in other mental health rehabilitation and treatment environments.