Siding Cost Calculator
Free siding cost calculator. Estimate material cost to side a house by vinyl, fiber cement, wood, or metal. No signup.
A siding cost calculator estimates the material cost of re-siding a house from its wall area, minus doors and windows, using typical per-square prices for vinyl, fiber cement, wood, and metal. It is a material-only starting figure, not a contractor quote.
How the estimate is built
wall area = 2 × (length + width) × height − openingssquares = wall area ÷ 100, because siding is priced per “square” of 100 ft²material = squares × price per squarewith waste = material × 1.10— the tool adds a fixed 10% for cuts and errors
The price per square comes from the selected material unless you type a custom figure, which overrides the default. Only the wall perimeter is measured; gable triangles and soffits are not included, so add them separately for an accurate total.
Worked example: a 40 × 30 ft house with 9 ft walls
Defaults: length 40 ft, width 30 ft, height 9 ft, 400 ft² of openings, vinyl siding at the default $280 per square.
| Step | Calculation | Result |
|---|---|---|
| Gross wall area | 2 × (40 + 30) × 9 | 1,260 ft² |
| Net wall area | 1,260 − 400 | 860 ft² |
| Squares | 860 ÷ 100 | 8.6 squares |
| Material | 8.6 × $280 | $2,408 |
| With 10% waste | $2,408 × 1.10 | $2,649 |
Switch the material and only the price per square changes: fiber cement at $400 would be 8.6 × $400 = $3,440, or $3,784 with waste. Installation labor is not included and typically adds 1.5 to 2 times the material cost.
Reference: material prices per square
| Siding type | Default price per 100 ft² | Material for 8.6 squares |
|---|---|---|
| Vinyl | $280 | $2,408 |
| Metal | $420 | $3,612 |
| Fiber cement | $400 | $3,440 |
| Wood / cedar | $550 | $4,730 |
These are the tool’s built-in defaults, intended as rough ranges rather than quotes. Local pricing swings with material grade, thickness, and freight, which is why the custom price field exists. Always compare against a real supplier figure when you have one.
What is a square of siding?
A square is 100 ft² of finished wall, the unit both suppliers and installers use. The calculator converts net wall area into squares before applying a price, which is why the same area gets very different totals by material. When you order, add the waste your supplier recommends on top, and keep a spare box or two for future repairs.
| House footprint | Wall area at 9 ft (no openings) | Squares |
|---|---|---|
| 30 × 20 | 900 ft² | 9.0 |
| 40 × 30 | 1,260 ft² | 12.6 |
| 50 × 30 | 1,440 ft² | 14.4 |
| 60 × 40 | 1,800 ft² | 18.0 |
What the estimate does not cover
Material is only the first line of a re-side. Scaffolding or ladders, removal and disposal of the old cladding, house wrap, flashing, corner and window trim, caulk, and fasteners all add up. Labour is the largest missing piece, typically one and a half to two times the material cost. Use the estimate to sanity-check quotes rather than as the final budget.
Common mistakes
- Ignoring gables and soffits. Perimeter times height misses triangular gable ends and the underside of eaves. Measure them and add them.
- Comparing material only. Cheap vinyl material can carry different installation and trim costs than fiber cement, so the installed totals are not in the same order.
- Forgetting trim. Corners, window surrounds, and fascia add real material and labor, often 10–20% of the job.
- Treating the result as a quote. This is the material starting number. Labor, scaffolding, disposal, and permits sit outside it.
How many squares of siding for a 40 × 30 house?
About 8.6 squares for the walls at 9 feet with 400 ft² of openings. That is 860 ft² of net wall area, or 9.5 squares once you allow 10% waste.
Is installation included in the estimate?
No. It is material only. Professional installation usually runs 1.5 to 2 times the material cost, so a $2,649 vinyl material estimate could become a $7,000–$8,000 installed job.
Does the calculator handle gable ends?
No. It measures the rectangular wall perimeter only. Calculate each triangular gable as base × height ÷ 2 and add the area in before relying on the figure.
Siding covers the walls the way the roofing cost calculator covers the top, both priced per square. For the outdoor living space, the deck cost calculator uses the same area-based approach.