Siding is used to cover the exterior of a building for protective and decorative purposes. These building products are made of a variety of materials. Choices include aluminum, brick, cedar, composite or engineering materials, fiber cement, steel, stone, stucco, vinyl, and wood. Typically, siding products include panels and panelized building systems as well as shingles and clapboards. When selecting siding, considerations include the square footage to cover, the type of maintenance required, color retention, and cost. Siding is available in a variety of colors, and may comply with standards from trade associations such as the Vinyl Siding Institute (VSI). With some products, the installation of a water-resistant barrier is recommended.

Aluminum siding, brick, cedar shingles, and engineered or composite wood are common choices for building exteriors. Aluminum siding is durable, fireproof, and cost-effective. Although it does not crack, this type of siding dents easily. Brick is more expensive than aluminum, but is designed to last for many years. Sometimes, brick veneer is used to reduce building costs. Cedar shingles are made of natural wood and stained in browns or grays. They require less maintenance than clapboard, which requires periodic painting. Siding made of engineered or composite wood is also available. Engineered materials are less expensive than wood, and come in long panels that are easy to install.  

Siding made of fiber cement, steel, stone, and stucco is also commonly available. Fiber cement siding looks like wood, but costs less and requires less maintenance. It resists fire and termites, and does not buckle, rot, or wrap. Although fiber cement siding is heavier than wood siding, the trim pieces are straighter and easy to handle. Steel siding does not require splicing during installation and can be cut to very exact measurements. Stone is the most durable siding product, but also the most expensive. To reduce costs, builders may opt for a pre-cast stone veneer and facing called culture stone. Stucco combines a very hard surface with moisture-resistance. Synthetic stucco resembles natural stucco, which is a combination of cement, water, and sand or lime.

Vinyl siding and wood siding are popular building materials. Vinyl siding is made from polyvinyl chloride (PVC), a common industrial plastic. Though relatively inexpensive, vinyl siding is often prone to cracking, splitting, and wear. Manufacturers have addressed these problems, however, and now provide durable vinyl siding in a variety of colors and styles. Wood siding is valued for its appearance, but requires periodic painting or staining to help protect against water damage. There are many types of products. Examples include clapboard, rectangular planking, plywood, shingles, shakes, and hardboard. Cedar, cypress, redwood, yellow pine, Douglas fir, and western red cedar are often used.