With the inner space around only 60 m², the designer tore down all old layout and restored to original, basic outline. Low privacy necessity for a single household increases the flexibility of functional arrangement by leading the sunlight and greenery into all spaces. Furthermore, the location of the building surrounded by mountains, the place in which reduces the barrier and reactivates the air convection, decreases the reliance on air conditioning and lamp. The goal of energy saving, environmental protection and loving the earth can be reached ultimately.