be utilized in parking lot, driveways, and playgrounds. Windbreak Planting or building windbreaks to slow winds near buildings, which reduces heat loss. Homes loses heat through infiltration in the Winter. Windbreaks should be designed to intercept and redirect the Winter winds before they reach the house and outdoor areas with playgrounds or sensitive plants. The windbreak in the Winter should also be designed so that they would not block the sunlight in the Winder or block the wind in the Summer. Wall sheltering with shrubbery or vines By plating shrubs near the wall, it creates an insulating dead air space around the wall. This is a similar idea with use tree windbreak. Shrub should be planted at least 2 feet from the wall to prevent moisture and insects problem. Taking advantage of natural landform Earth sheltering is an example of utilizing natural landform and geological condition to save energy in building a structure. It is believed to save energy in multiple ways: by using the rock or strong soil as wall and ground as the floor, construction cost is greatly reduced, because the structure will need less load bearing material and there is no need for excavation and foundation construction; the wall and the floor made of natural material likely will have better insulation than artificial wall and floors; Natural walls and floors can also reduce fire hazard, because they are hard to be ignited thus reduce the need for flame retardants. In a study of simulating a structure with varying depth submerged in the ground to understand the insulating effect of natural wall and ground in cold climate, it was found that the thermal transmittance of the earth-sheltered walls and floor is 16% - 45% lower than that of the structure totally above ground. Other than Earth Sheltering, a simpler way of taking advantage of natural landform is using geology, such as mountains, for shade. Green roofs Often, landscape design and architecture refers to the design in ground surface; in many contexts, specifically, the design guidance and topics are for a typical residential landscape in suburban housing, where there is a yard (garden), a driveway, and a house. In the crowded urban area, however, there is not abundant ground surface for landscape design. Green roofs, then, become an appealing option to add some aesthetics and green to the crowded cities. Not limited to the cities, green roofs can be