Everyday design solutions often cause unnecessary levels of discomfort or even exclusion, affecting mainly older adult users and people of all ages with a variety of functional impairments. Designers' intuitive and informal approaches to the evaluation of product usability and accessibility attributes are insufficient when addressing the needs of a wider population. This paper discusses the advantages of using more formal assessment approaches throughout the entire design process. A case study on domestic appliances illustrates the comparison between the implementation of three different assessment methods.@en