The increasing diversity of materials creates many possibilities and constraints that designers have to consider when selecting materials for projects. While the literature has investigated materials selection in engineering, product, and architectural design, knowledge is still lacking in interior design. Accordingly, this study focused on interior finishing materials with three objectives: (1) explore the determinants of materials selection in interior design, and within the residential design context, (2) identify designers’ finishing material preferences and selection criteria for floors, walls, and ceilings; (3) investigate designers’ criteria prioritizations while selecting materials. For this we conducted one-to-one interviews with architects and interior designers specializing in residential spaces. We first explored their material selection considerations in general. Second, we documented their material designations in residential project entry halls they had designed along with their selection criteria. Third, we presented an entry hall of a residential space for them to choose the materials while we questioned them about their materials selection priorities. The results reveal that the main determinants of materials selection include material-related, project-related, and designer-related factors. Moreover, materials choices and selection criteria vary between surfaces in space. Finally, the designers give the most priority to sensorial properties and the least to ecological properties. These findings expand our knowledge about materials in interior design, enhance the knowledge base for materials education, and have implications for designers and manufacturers regarding selecting and designing finishing materials.