HC House is a residential project of a small family in the urban area in Ha Tinh city, Ha Tinh province. We developed this project by connecting family routines, hobbies, professional characteristics and some memories of the old house where they lived in many years ago. This is a townhouse which is a typical type of residential project in Vietnam. Its dimensions is 7.5x19m, the facade is the only open area. The unique context and site constrain create challenges for the designer to create a space that is the modest and the most natural ventilation.