By ON Architects, Train House is a small house for a couple with elderly parents. The challenging topography of the site meant that there was little in the way of exterior space in which to enjoy the surroundings and hence a courtyard approach was adopted.

The house includes three courtyards, each with a different character. The client’s and the parents’ living areas are separate to maintain their own autonomy, while semi-porous outdoor courtyards allow communication in between. Insertion of space where one can see the sky enables connectivity with light and fresh air everywhere in the house.

The master bedroom itself has its own small courtyard to ensure the couple’s independence but also connects to the main courtyard to enable communication with the parents at any time.

The surface of the building is finished with exposed concrete as an expression of the rough texture of old tree bark used in a Korean traditional house. In order to achieve this effect, the architect conducted extensive experiments and research on pure materiality.

As a result, the building gained expressive facades reflecting daylight in various angles and gradually changing the colour and impression of the concrete over time.