How much siding do I need?
Estimate the number of siding pieces needed for exterior walls based on wall area and siding exposure.
Siding calculator
Choosing the Right Siding Material
Siding material determines your home's exterior appearance, insulation value, and maintenance requirements. Consider climate, architectural style, and long-term upkeep.
Vinyl Siding: The most popular residential siding due to its low cost and minimal maintenance. Vinyl never needs painting, resists moisture and insects, and comes in many colors and profiles (lap, shake, board-and-batten). Can crack in extreme cold and may fade over time.
Fiber Cement (HardiePlank): A durable blend of cement, sand, and cellulose fibers. Fiber cement resists fire, termites, rot, and impact. Holds paint well for 10–15 years and mimics wood grain beautifully. Heavier than vinyl and requires professional installation.
Wood Siding: Classic, natural beauty with options including cedar shingles, clapboard, and board-and-batten. Wood provides excellent insulation and can be painted or stained. Requires regular maintenance (painting or staining every 3–7 years) and is susceptible to rot and insects.
Metal Siding (Steel / Aluminum): Durable and fire-resistant. Aluminum is lightweight and rust-proof; steel is stronger but can rust if scratched. Metal siding is often used for modern, industrial, or coastal homes. Energy-efficient and recyclable.
Siding Material Cheat Sheet
Use this reference to choose the right siding:
| Material | Maintenance | Lifespan | Cost |
|---|---|---|---|
| Vinyl | Low (power wash occasionally) | 20–40 years | $ |
| Fiber Cement | Moderate (paint every 10–15 years) | 50+ years | $$ |
| Wood | High (stain/paint every 3–7 years) | 20–40 years | $$$ |
| Metal | Low (occasional cleaning, touch-up paint) | 40–70 years | $$$ |
Siding types and exposure
- Vinyl siding: 4 inches exposure standard, varies by profile
- Wood lap siding: 4-6 inches exposure depending on board width
- Fiber cement: 4-5 inches exposure, typically 6.25 or 8.25 inch planks
- Board and batten: 8-12 inch board spacing
Add 10% for waste, cuts, and gable ends. For walls with many windows and doors, subtract the rough opening area before calculating.
Worked example
For example, for a 20×10 ft wall, 4-in exposure lap siding:
- Wall area = 20 × 10 = 200 sq ft
- Pieces needed = (200 × 12) ÷ (4 × 20) = 2400 ÷ 80 = 30 pieces
- Add 10% for waste, starter strips, and corners: 33 pieces
- Also order J-channel around windows, corner trim, and starter strip
Common mistakes
| Mistake | Why it matters |
|---|---|
| Not accounting for window and door trim | Subtract rough openings but add J-channel and corner trim to your materials list |
| Starting with a level course | The first course must be perfectly level — any tilt amplifies as you go up |
| Nailing too tight | Leave 1/32-in gap between nail head and siding to allow for thermal expansion |