PROGRAM:The L71 house is a single family house located on the northeastern side of Bangkok, Thailand. The site for the house is a long and narrow shape site. All of the house programs such as 4 bedrooms, dining room, and family room are place along the site to face north direction. Since the owners have some parties occasionally, the public areas, such as living room and parking, are in the front of the house, and the private areas are in the back of the house along with a swimming pool. EXTEND:The living room mass was extended to create private space for the swimming pool and the second floor mass was extended to create shading for the swimming pool and terrace. SPLIT: If the house is designed as one big mass it will block ventilation and natural light, so in this house each room is spitted to maximize ventilation and natural light.INSERT: Since the masses are splitted, it creates some semi outdoor space to interlock indoor and outdoor space. Varieties of natural materials including water, grass and wood are inserted into each space. COVER:The roof of the main house is double-roof to cover the house from weather. The lower roof is reinforced concrete slab, and the upper roof is metal sheet roof. A space between the two layers of roof acts as an air buffer, natural ventilation and allows for easy maintenance. MATERIALS: Main material of this house is painted plastered brick wall and tint glass. Where the masses are splitted, the material of the splitted masses is wood.