What is Siding Made of: Complete Guide for Homeowners

Walk down any American street and you’ll see five or six different siding materials within a single block, each making different promises about durability, maintenance, and weather resistance. Understanding what is siding made of matters because the substrate dictates installation cost, lifespan, fire rating, and how it weathers in your specific climate. This guide breaks down every common siding type, what’s actually inside the panel, and where each one earns its keep.

Vinyl Siding: PVC With a Few Additives

Roughly 27 percent of new American homes get vinyl, which makes it the most installed exterior cladding in the country. The base resin is polyvinyl chloride (PVC) mixed with titanium dioxide for UV resistance, calcium carbonate as a filler, tin or lead stabilizers in older formulas, and color pigments throughout the panel. Quality varies dramatically by thickness — economy grades run 0.040 inches while premium lines from CertainTeed Monogram or Mastic Quest hit 0.046 to 0.052 inches.

Expect $4 to $8 per square foot installed. Vinyl handles UV exposure for 25 to 40 years, but it warps near grills and dark roofs that reflect heat onto the wall.

Fiber Cement: Portland Cement, Sand, Cellulose

James Hardie pioneered the modern fiber cement category, and the recipe is straightforward: roughly 90 percent Portland cement and sand mixed with 8 to 10 percent cellulose wood fiber for tensile strength. The slurry is pressed into planks, cured in an autoclave, then primed and optionally painted at the factory using Hardie’s ColorPlus or LP’s SmartGuard finishes.

The result is a 5/16 inch thick board that resists fire, termites, hail, and rot. Installed cost runs $8 to $14 per square foot. Hardie planks come with a 30-year non-prorated warranty, and Class 1A fire ratings make fiber cement standard in wildfire-prone California neighborhoods.

Engineered Wood: Wood Strands and Resin

LP SmartSide dominates this category. The boards are made by shredding southern yellow pine into strands, treating them with zinc borate to repel termites and fungal decay, blending with phenolic resin and waxes, then hot-pressing into planks. The finished product looks like real cedar but costs $5 to $9 per square foot installed.

Engineered wood holds paint extremely well and accepts nails without splitting. The trade-off is moisture sensitivity at cut ends — every field cut needs to be sealed with a compatible primer, or the resin matrix swells. Backed by 50-year prorated warranties when installed per spec.

Cedar and Redwood: Solid Natural Lumber

The original American siding. Western red cedar and California redwood both contain natural oils (thujaplicin in cedar, tannins in redwood) that resist insects and decay. Common profiles include 1×6 tongue-and-groove, 1×8 channel rustic, and 5/8-inch bevel lap. Premium clear vertical-grain cedar runs $7 to $12 per board foot before installation; the finished wall lands at $10 to $18 per square foot installed.

Wood demands maintenance. Plan on staining or oiling every 3 to 5 years with a product like Sikkens Cetol or Penofin Verde. Skip the schedule and you’ll see graying within 12 months and active rot within a decade.

Aluminum and Steel: Coated Metal Panels

Steel siding from manufacturers like ABC Seamless and Edco starts as cold-rolled galvanized coil, then receives a Kynar 500 PVDF coating with ceramic pigments. Aluminum versions skip the galvanizing since the base metal won’t rust. Both come in horizontal lap, vertical board-and-batten, and standing seam profiles.

Metal cladding excels in coastal hurricane zones (rated to 160+ mph wind uplift) and wildfire interfaces. Cost runs $6 to $12 per square foot for aluminum, $8 to $16 for steel. Dents on aluminum from baseballs or hail can be a real problem; steel is much more impact resistant.

Stucco: Cement, Sand, Lime Over Lath

Traditional three-coat stucco is a wet system: a scratch coat and brown coat of Portland cement, sand, and lime are troweled over galvanized metal lath and building paper, then finished with an acrylic-modified color coat from manufacturers like Sto, Dryvit, or Parex. Total thickness reaches 7/8 inch over wood framing.

Stucco runs $7 to $12 per square foot installed. It’s seamless, fire resistant, and lasts 50 to 80 years when flashed properly. The catch is moisture management — improperly detailed stucco walls in cold climates have led to multi-million-dollar class action settlements.

Brick and Stone Veneer: Real and Manufactured

Traditional brick veneer is a 4-inch nominal wythe of clay-fired brick anchored to the framing with corrugated metal ties, with a 1-inch air gap and weep holes. Cost runs $14 to $20 per square foot. Manufactured stone veneer from Eldorado Stone or Cultured Stone is made by casting Portland cement, lightweight aggregate, and iron oxide pigments into molds shaped like real stone. Thinner and lighter, it installs over plywood with metal lath and mortar at $12 to $18 per sq ft.

Choosing the Right Siding for Your Climate

Fiber cement and brick top the durability charts almost everywhere. Vinyl makes sense for budget-conscious Midwest projects. Engineered wood balances curb appeal and price across most of the country. Metal earns its premium in coastal and wildfire zones. And solid cedar still looks right on a Pacific Northwest craftsman if you’re willing to maintain it.

Whatever you pick, the underlayment matters as much as the cladding. A quality housewrap like Tyvek CommercialWrap, properly flashed window openings, and a rain screen gap behind absorbent materials separate a 50-year wall from a 15-year repair bill.

Trim, Soffit, and Accent Materials

Siding rarely covers the entire wall on its own. Window trim, corner boards, frieze boards, and soffits all play a role in the final exterior. PVC trim from Versatex and AZEK handles weather better than wood for most regions and eliminates rot at end grain and joints. Aluminum coil stock wraps wood trim for low-maintenance fascia and soffit details. Stone water tables along the foundation transition reduce splashback that erodes lower siding faster than any other location on the wall.