Roofing Shingles Calculator
function calculateRoofing() {
var length = parseFloat(document.getElementById('roofLength').value);
var width = parseFloat(document.getElementById('roofWidth').value);
var pitchFactor = parseFloat(document.getElementById('roofPitch').value);
var wasteFactor = parseFloat(document.getElementById('wasteFactor').value);
if (isNaN(length) || isNaN(width) || length <= 0 || width <= 0) {
alert("Please enter valid positive numbers for length and width.");
return;
}
if (isNaN(wasteFactor) || wasteFactor < 0) {
wasteFactor = 0;
}
// Calculation Logic
var baseArea = length * width;
var actualSurfaceArea = baseArea * pitchFactor;
var totalAreaWithWaste = actualSurfaceArea * (1 + (wasteFactor / 100));
var squares = totalAreaWithWaste / 100;
var bundles = Math.ceil(totalAreaWithWaste / 33.333);
// Update UI
document.getElementById('totalArea').innerText = actualSurfaceArea.toLocaleString(undefined, {maximumFractionDigits: 0}) + " sq ft";
document.getElementById('areaWithWaste').innerText = totalAreaWithWaste.toLocaleString(undefined, {maximumFractionDigits: 0}) + " sq ft";
document.getElementById('roofSquares').innerText = squares.toFixed(2) + " sqs";
document.getElementById('bundlesNeeded').innerText = bundles.toLocaleString();
// Show Results
document.getElementById('roofResults').style.display = 'block';
// Smooth scroll to results
document.getElementById('roofResults').scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}