siding

Siding is exterior cladding applied to the outside of a building to shed water, resist weather, and contribute to insulation and appearance. It is typically installed over a structural layer and a weather-resistant barrier, and it is designed to shed rain and protect the wall cavity while allowing the wall assembly to dry.

The most common siding materials are vinyl, wood, fiber cement, metal, and composite products. Vinyl siding is lightweight, low maintenance, and affordable, but can fade, crack, or dent. Wood siding offers a natural look but requires regular painting or staining and is susceptible to rot, pests, and moisture damage. Fiber cement siding mimics wood while providing greater resistance to rot and fire; it is durable but heavier and may require specialized installation. Metal sidings, such as steel or aluminum, provide durability and a modern appearance with low maintenance, though coating integrity and denting can be concerns. Composite or engineered wood siding blends materials to balance appearance, maintenance, and cost.

Installation involves a weather-resistant barrier, proper flashing around openings, and ventilation to prevent moisture buildup. Panels or boards are fastened with corrosion-resistant nails or screws, allowing for expansion and contraction. Maintenance includes periodic cleaning, repainting or resealing wood, caulking gaps, and inspecting for moisture intrusion, rot, or damage.

Lifespan varies by material: vinyl typically 20–40 years; wood 20–60 with maintenance; fiber cement 30–50; metal 40–70. Siding choices influence curb appeal, durability, and energy performance, and they have environmental implications regarding production, installation, and end-of-life disposal.

See also: exterior cladding, weatherization, building envelope.