by the walls of the structure itself. Drained cladding also known as screened walls acknowledges moisture will penetrate the cladding so a moisture barrier such as housewrap or felt paper inside the cladding provides a second line of defense and sometimes a drainage plane or air gap allows a path for the moisture to drain down through and exit the wall. Sometimes ventilation is provided in addition to the drainage plane such as in rainscreen construction. Face-sealed also called barrier wall or perfect barrier cladding relies on maintaining a leak-free surface of the cladding. Examples of face sealed cladding are the early exterior insulation finishing systems, structural glazing, metal clad panels, and corrugated metal. Building walls frequently become works of art, externally and internally, such as when featuring mosaic work or when murals are painted on them; or as design foci when they exhibit textures or painted finishes for effect. Curtain wall In architecture and civil engineering, curtain wall refers to a building facade that is not load-bearing but provides decoration, finish, front, face, or historical preservation. Precast wall Precast walls are walls which have been manufactured in a factory and then shipped to where it is needed, ready to install. It is faster to install compared to brick and other walls and may have a lower cost compared to other types of wall. Precast walls are cost effective compare to Brick Wall compound wall. Mullion wall Mullion walls are a structural system that carries the load of the floor slab on prefabricated panels around the perimeter. Partition wall A partition wall is a usually thin wall that is used to separate or divide a room, primarily a pre-existing one. Partition walls are usually not load-bearing, and can be constructed out of many materials, including steel panels, bricks, cloth, plastic, plasterboard, wood, blocks of clay, terracotta, concrete, and glass. Some partition walls are made of sheet glass. Glass partition walls are a series of individual toughened glass panels mounted in wood or metal framing. They may be suspended from or slide along a robust aluminium ceiling track. The system does not require the use of a floor guide, which allows easy operation and an uninterrupted threshold. A timber partition consists of a wooden framework, supported on the floor or by side walls. Metal lath and plaster, properly laid, forms a reinforced partition wall. Partition walls constructed from fibre cement backer