This house is high-quality ready-made "pret-a-porter" type. The total floor area is 79.3 m2. And the form is a 7.3-meter complete cube.The light court which is in the inside of the cube covers the 1/4 of the total floor space.There is no large aperture into the facade other than the entrance because lighting and ventilation were taken by light court.There are small windows designed as an accent and as an air vent. Those windows are arranged on 4*4 grids.This house is the most suitable in the case of the following condition. 1) The area have to care privacy and security. 2) The land is smaller than 100M2.Here is a light court, a loft and a rooftop terrace inside of the cube, and the inside space is felt very widely because the second floor is double height.The minimum building cost of this house is 15,000,000 yen.This is built by "a traditional method of construction" that is the traditional method of construction of the Japanese wooden building.It is recommended about the environment conservation to make a house using the domestic Japanese wood which is recyclable material.This house can put a solar panel on the roof. In addition, exterior wall of house can make green. This design can contribute to the urban tree-planting.