Korean housing policies and market have come to center on apartment housing, because the country’s rapid urbanization process has demanded a supply of mass housing units. Consequently, the quality of large complex apartment housing has improved over time, and people can now buy quality apartments with confidence, since they are constructed through an institutionalized supply process that involves medium- to large-scale companies. On the other hand, small single- and multi-family houses, each built on an individual lot by an architect and a builder at the owner’s request, do not follow a systematic supply process, hindering realization of uniform quality. Also, when these small houses encounter problems in their performance or require refurbishing and/or retrofitting, the owners (or the residents), often lacking in expertise, tend to have difficulties in finding solutions and are burdened with extra cost in reality.