Cladding systems (siding) are exterior materials attached to the building structure providing weather protection and aesthetic appearance. Common cladding materials include vinyl, fiber cement, wood, and composite materials. Vinyl siding is economical and low-maintenance, consisting of rigid PVC planks with interlocking joints. Vinyl is durable and does not require painting, though color may fade over time. Vinyl siding expands and contracts significantly with temperature; installation must allow for movement with expansion/contraction joints. Fiber cement siding combines Portland cement with wood fibers, providing durability and paint-ability. Fiber cement is more rigid than vinyl and resists warping. It is heavier than vinyl and more difficult to install. Wood siding provides traditional appearance and is renewable but requires regular painting and is susceptible to rot and insect damage. Composite materials combining wood fibers with plastic binders offer some advantages of wood appearance with improved durability. Installation typically begins with drainage plane (felt or synthetic paper) behind the cladding to protect the structure from water penetration. Cladding is fastened directly to the sheathing or to furring strips. Fastener spacing and type affect system performance. Thermal insulation boards may be installed behind cladding to improve energy performance. Movement joints accommodate expansion and contraction. Corner trim, around windows and doors, and at transitions must be detailed carefully to prevent water penetration. Water penetration behind cladding causes deterioration of the structure. Proper flashing above windows and at vertical transitions directs water away from the structure. Cladding maintenance includes periodic washing, painting (if wood), and inspection for damage.