Calculate how much siding you need for your home's exterior. Supports vinyl, fiber cement, wood, and engineered wood siding. Includes trim, starter strip, and accessory estimates.
Estimates only — actual quantities depend on siding exposure, overlap, and house geometry.
Residing a 40×30 foot single-story house with 9-foot walls, 2 doors, and 8 windows? Gross wall area is 1,260 square feet. Subtract 42 sqft for doors and 120 sqft for windows, leaving 1,098 sqft of siding area. With 10% waste, that's about 13 squares (1,300 sqft). At $150–$300 per square for vinyl installed, the project runs $1,950–$3,900 in materials.
| Siding Type | Material / Square | Installed / Square |
|---|---|---|
| Vinyl | $60–$120 | $150–$300 |
| Fiber Cement (HardiePlank) | $100–$200 | $300–$500 |
| Wood Lap | $150–$300 | $400–$700 |
| Engineered Wood (LP SmartSide) | $80–$150 | $250–$400 |
Measure the height and length of each exterior wall, multiply to get square footage, then subtract doors (21 sqft each) and windows (15 sqft each). Add 10% for waste. Divide by 100 to get the number of squares.
100 square feet of coverage area, same as roofing. A 1,200 sqft house exterior needs about 12 squares plus waste.
Materials run $60–$120 per square. Professional installation adds $90–$180 per square for labor. A typical 1,200 sqft house costs $1,800–$3,600 for materials or $4,000–$8,000 installed.
20–40 years depending on quality and climate. Fiber cement lasts 30–50 years. Wood siding lasts 20–30 years with regular painting and maintenance.
Not always. Vinyl and fiber cement can often be installed over existing siding if the wall is flat and the old siding is in reasonable condition. Removing old siding adds $1,000–$3,000 but allows inspection of sheathing and housewrap underneath.
Typical Results
💡 If the siding quantity seems high, verify you entered wall area — not total house square footage.
Common Mistakes