Housing is one of the primary human needs. In some areas, housing is found not only as a dwelling space but also as a commercial space where the house is used as a business activity has an impact on the residential spatial function. This research examines the effect of spatial function transformations in residential spaces into commercial spaces on the value of residential properties. Although this case study was designated as residential, its location may be quite strategic where it became a route crossed by many people to reach public places. The occupants recognized the potential to open a commercial business because the surrounding area was quite crowded. The research method is a case study research with descriptive qualitative analysis techniques. This research focused on the utility aspects that affect the property value of case study. The transformation from residential to commercial spatial function has impacted the utility aspect of property value. The existence of commercial space in commercial houses affected the house’s primary function, where the addition of commercial space decreased the value of the house’s function as identity and security. Based on the analysis, it was found that the property value of residential houses had a higher value than commercial houses in the utility aspect. The transformation in spatial function impacted the utility aspect, where the property value of commercial houses in the utility aspect had decreased.