Installing new siding is a significant home improvement project. Fiber cement siding, particularly James Hardie's popular Hardie Plank, offers a durable, attractive, and low-maintenance option. To accurately budget for this investment, it's crucial to understand the various cost components involved. This calculator helps you estimate the total project cost based on key factors like material prices, labor, and waste.
Key Cost Factors Explained:
Total Wall Area to Cover (sq ft): This is the most fundamental measurement. It represents the total surface area of your home's exterior walls that will be covered with siding. Accurately measuring this, often by multiplying the length of each wall by its height and summing them up (subtracting window and door areas if you want a precise material calculation, though for waste estimation, full wall area is often used), is the first step in estimating material needs.
Hardie Plank Cost per Square Foot ($): This refers to the price of the fiber cement siding panels themselves. Prices can vary based on the specific product line (e.g., HardiePlank® Lap, HardieShingle®, HardiePanel®), the color chosen, and the texture. It's essential to get quotes from suppliers for the exact product you intend to use.
Installation Labor Cost per Square Foot ($): Labor is a substantial part of the total cost. Experienced siding installers are needed to properly cut, fit, and fasten fiber cement boards, ensuring a weather-tight and aesthetically pleasing finish. This cost can fluctuate significantly based on your geographic location, the complexity of your home's architecture (e.g., multiple stories, numerous corners, dormers), and the prevailing labor rates in your area.
Trim & Accessories Cost per Linear Foot ($): Siding projects require trim boards for corners, around windows, doors, and along rooflines. These can also be made from fiber cement or other materials. This metric accounts for the cost of these trim pieces and any associated accessories like starter strips or color-matched caulking per linear foot.
Total Linear Footage of Trim (ft): This measures the total length of all the trim pieces required for the project. Similar to wall area, this is calculated by measuring the perimeter of all areas that will receive trim.
Waste Factor (%): It's standard practice to account for material waste during installation. This occurs due to cutting boards to fit around obstacles, miscuts, or damaged pieces. A typical waste factor for siding installation ranges from 5% to 15%. Including this percentage ensures you order enough material to complete the job without running short.
How the Calculator Works:
The calculator uses the following formulas to estimate your total siding cost:
Material Cost: (Total Wall Area * Hardie Plank Cost per Sq Ft) * (1 + Waste Factor / 100)
Labor Cost: Total Wall Area * Installation Labor Cost per Sq Ft
Trim Cost: Total Linear Footage of Trim * Trim & Accessories Cost per Linear Foot
Total Estimated Cost: Material Cost + Labor Cost + Trim Cost
This calculator provides an estimate. Actual costs can vary. Always obtain detailed quotes from multiple reputable siding contractors for the most accurate pricing for your specific project. Consider factors like permits, scaffolding, disposal of old siding, and potential repairs to the underlying wall structure, which may not be included in this basic estimate.
function calculateSidingCost() {
var totalSquareFootage = parseFloat(document.getElementById("totalSquareFootage").value);
var hardiePlankCostPerSqFt = parseFloat(document.getElementById("hardiePlankCostPerSqFt").value);
var installationCostPerSqFt = parseFloat(document.getElementById("installationCostPerSqFt").value);
var trimCostPerLinearFt = parseFloat(document.getElementById("trimCostPerLinearFt").value);
var trimLinearFootage = parseFloat(document.getElementById("trimLinearFootage").value);
var wasteFactor = parseFloat(document.getElementById("wasteFactor").value);
var resultValueElement = document.getElementById("result-value");
// Clear previous results
resultValueElement.textContent = "$0.00";
// Validate inputs
if (isNaN(totalSquareFootage) || totalSquareFootage <= 0 ||
isNaN(hardiePlankCostPerSqFt) || hardiePlankCostPerSqFt < 0 ||
isNaN(installationCostPerSqFt) || installationCostPerSqFt < 0 ||
isNaN(trimCostPerLinearFt) || trimCostPerLinearFt < 0 ||
isNaN(trimLinearFootage) || trimLinearFootage < 0 ||
isNaN(wasteFactor) || wasteFactor < 0) {
alert("Please enter valid positive numbers for all fields.");
return;
}
// Calculate Material Cost
var adjustedSquareFootageForWaste = totalSquareFootage * (1 + wasteFactor / 100);
var materialCost = adjustedSquareFootageForWaste * hardiePlankCostPerSqFt;
// Calculate Labor Cost
var laborCost = totalSquareFootage * installationCostPerSqFt;
// Calculate Trim Cost
var trimCost = trimLinearFootage * trimCostPerLinearFt;
// Calculate Total Estimated Cost
var totalEstimatedCost = materialCost + laborCost + trimCost;
// Display the result
resultValueElement.textContent = "$" + totalEstimatedCost.toFixed(2);
}
function resetForm() {
document.getElementById("totalSquareFootage").value = "";
document.getElementById("hardiePlankCostPerSqFt").value = "";
document.getElementById("installationCostPerSqFt").value = "";
document.getElementById("trimCostPerLinearFt").value = "";
document.getElementById("trimLinearFootage").value = "";
document.getElementById("wasteFactor").value = "";
document.getElementById("result-value").textContent = "$0.00";
}