Estimate the cost and quantity of shingles needed for your roof project.
sq ft
sq ft/bundle
%
$
Understanding Your Shingles Roof Estimate
Replacing or installing a new roof is a significant investment. Our Shingles Roof Calculator provides a quick and easy way to estimate the materials and costs involved. This calculator considers the total area of your roof, the coverage provided by each bundle of shingles, an allowance for waste, and the price per bundle.
How the Calculator Works:
The calculation involves several key steps to ensure an accurate estimate:
Total Shingles Needed: First, we determine the raw amount of shingles required to cover your roof's area.
Bundles Required: We then divide the total shingle requirement by the coverage area of a single bundle to find out how many bundles you'll need.
Accounting for Waste: Roofing projects inevitably involve cutting and fitting shingles, leading to waste. The waste factor percentage is applied to the raw shingle quantity to account for this, ensuring you order enough material to complete the job without running short. This is crucial for avoiding extra trips to the store and potential delays.
Total Cost: Finally, the total number of bundles (including waste) is multiplied by the price per bundle to give you an estimated total material cost.
Key Input Factors Explained:
Roof Area (sq ft): This is the total square footage of your roof that needs to be covered by shingles. For complex roof shapes, it's often best to consult a professional or use specialized roof measurement tools for accuracy.
Shingle Coverage per Bundle (sq ft/bundle): Most asphalt shingles are sold in bundles that cover approximately 33.3 sq ft. Always check the manufacturer's specifications for the exact coverage.
Waste Factor (%): A standard waste factor for asphalt shingles is typically between 5% and 15%. Steeper roofs, complex rooflines, and dormers may require a higher waste factor. 10% is a common starting point for estimation.
Price per Bundle ($): This is the cost of a single bundle of shingles. Prices vary significantly based on shingle type (3-tab, architectural, designer), brand, and your local market.
Why This Matters:
Accurate material estimation is vital for budgeting your roofing project effectively and ensuring a smooth installation process. While this calculator provides a valuable estimate, it's always recommended to get quotes from professional roofing contractors who can provide a precise assessment and factor in labor costs, underlayment, flashing, ventilation, and other essential components of a complete roofing system.
function calculateRoofCosts() {
var roofArea = parseFloat(document.getElementById("roofArea").value);
var shingleCoverage = parseFloat(document.getElementById("shingleCoverage").value);
var wasteFactor = parseFloat(document.getElementById("wasteFactor").value);
var bundlePrice = parseFloat(document.getElementById("bundlePrice").value);
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = "; // Clear previous results
// Validate inputs
if (isNaN(roofArea) || roofArea <= 0) {
resultDiv.innerHTML = "Please enter a valid roof area (greater than 0).";
return;
}
if (isNaN(shingleCoverage) || shingleCoverage <= 0) {
resultDiv.innerHTML = "Please enter valid shingle coverage per bundle (greater than 0).";
return;
}
if (isNaN(wasteFactor) || wasteFactor < 0) {
resultDiv.innerHTML = "Please enter a valid waste factor (0% or greater).";
return;
}
if (isNaN(bundlePrice) || bundlePrice < 0) {
resultDiv.innerHTML = "Please enter a valid price per bundle (0 or greater).";
return;
}
// Calculations
var totalShinglesNeededRaw = roofArea;
var bundlesToCoverRoof = totalShinglesNeededRaw / shingleCoverage;
var wasteAmount = (totalShinglesNeededRaw * (wasteFactor / 100));
var totalShinglesWithWaste = totalShinglesNeededRaw + wasteAmount;
// Calculate total bundles, rounding up to the nearest whole bundle
var totalBundlesRequired = Math.ceil(totalShinglesWithWaste / shingleCoverage);
var estimatedTotalCost = totalBundlesRequired * bundlePrice;
// Display results
resultDiv.innerHTML = `
Estimated Roofing Costs
Bundles Required: ${totalBundlesRequired}
Estimated Material Cost: $${estimatedTotalCost.toFixed(2)}
`;
}