function calculateMetalRoofCost() {
var roofLength = parseFloat(document.getElementById('roofLength').value);
var roofWidth = parseFloat(document.getElementById('roofWidth').value);
var roofRise = parseFloat(document.getElementById('roofRise').value);
var roofRun = parseFloat(document.getElementById('roofRun').value);
var panelCostPerSqFt = parseFloat(document.getElementById('panelCostPerSqFt').value);
var laborCostPerSqFt = parseFloat(document.getElementById('laborCostPerSqFt').value);
var underlaymentCostPerSqFt = parseFloat(document.getElementById('underlaymentCostPerSqFt').value);
var fastenerTrimCostPerSqFt = parseFloat(document.getElementById('fastenerTrimCostPerSqFt').value);
var wasteFactor = parseFloat(document.getElementById('wasteFactor').value);
if (isNaN(roofLength) || isNaN(roofWidth) || isNaN(roofRise) || isNaN(roofRun) || isNaN(panelCostPerSqFt) || isNaN(laborCostPerSqFt) || isNaN(underlaymentCostPerSqFt) || isNaN(fastenerTrimCostPerSqFt) || isNaN(wasteFactor) || roofLength <= 0 || roofWidth <= 0 || roofRun <= 0 || roofRise < 0 || panelCostPerSqFt < 0 || laborCostPerSqFt < 0 || underlaymentCostPerSqFt < 0 || fastenerTrimCostPerSqFt < 0 || wasteFactor < 0) {
document.getElementById('metalRoofResult').innerHTML = '
Please enter valid positive numbers for all fields.
';
return;
}
// Calculate roof surface area multiplier based on pitch
var slope = roofRise / roofRun;
var surfaceAreaMultiplier = Math.sqrt(1 + (slope * slope));
// Calculate base roof area (footprint)
var baseArea = roofLength * roofWidth;
// Calculate actual roof surface area
var actualSurfaceArea = baseArea * surfaceAreaMultiplier;
// Calculate total area including waste for materials
var totalAreaWithWaste = actualSurfaceArea * (1 + (wasteFactor / 100));
// Calculate individual costs
var materialCost = totalAreaWithWaste * panelCostPerSqFt;
var laborCost = actualSurfaceArea * laborCostPerSqFt; // Labor usually based on actual surface area
var underlaymentCost = totalAreaWithWaste * underlaymentCostPerSqFt;
var fastenerTrimCost = actualSurfaceArea * fastenerTrimCostPerSqFt; // Fasteners/trim based on actual surface area
// Calculate total estimated cost
var totalEstimatedCost = materialCost + laborCost + underlaymentCost + fastenerTrimCost;
// Display results
document.getElementById('resultSurfaceArea').innerHTML = 'Estimated Roof Surface Area: ' + actualSurfaceArea.toFixed(2) + ' sq ft';
document.getElementById('resultMaterialCost').innerHTML = 'Estimated Material Cost: $' + materialCost.toFixed(2);
document.getElementById('resultLaborCost').innerHTML = 'Estimated Labor Cost: $' + laborCost.toFixed(2);
document.getElementById('resultUnderlaymentCost').innerHTML = 'Estimated Underlayment Cost: $' + underlaymentCost.toFixed(2);
document.getElementById('resultFastenerTrimCost').innerHTML = 'Estimated Fastener & Trim Cost: $' + fastenerTrimCost.toFixed(2);
document.getElementById('resultTotalCost').innerHTML = 'Total Estimated Cost: $' + totalEstimatedCost.toFixed(2);
}
Understanding Your Metal Roof Cost with Our Calculator
A metal roof is a significant investment that offers durability, energy efficiency, and a long lifespan. Understanding the potential costs involved is crucial for budgeting and planning your project. Our Metal Roof Cost Calculator provides a detailed estimate based on key factors specific to your roof.
How to Use the Metal Roof Cost Calculator
To get an accurate estimate, simply input the following details about your roof and project:
Roof Length (feet): The measurement of your roof from eave to eave along its longest side.
Roof Width (feet): The measurement of your roof from gable to gable along its shorter side.
Roof Rise (inches): This is the vertical measurement of your roof's slope. For example, a "6/12 pitch" means the roof rises 6 inches for every 12 inches of horizontal run. Enter '6' for a 6/12 pitch.
Roof Run (inches): This is the horizontal measurement of your roof's slope, typically 12 inches. Enter '12' for a standard pitch.
Metal Panel Cost per Sq Ft ($): The estimated cost of the metal roofing material itself per square foot. This varies widely based on material type (steel, aluminum, copper), gauge, finish, and panel style (standing seam, corrugated, shingle).
Labor Cost per Sq Ft ($): The cost charged by installers per square foot of roof surface. This can vary by region, roof complexity, and the specific contractor.
Underlayment Cost per Sq Ft ($): The cost of the protective layer installed beneath the metal panels, which adds an extra barrier against moisture.
Fastener & Trim Cost per Sq Ft ($): An estimated cost for all necessary fasteners, clips, flashing, ridge caps, gable trim, and other accessories required for a complete installation.
Waste Factor (%): An allowance for material waste due to cuts, errors, or complex roof designs. A typical waste factor is 5-15%.
Factors Influencing Metal Roof Costs
The total cost of a metal roof can fluctuate significantly based on several variables:
Material Type: Steel is generally the most affordable, followed by aluminum. Copper and zinc are premium options with higher costs.
Panel Style: Standing seam roofs are often more expensive than exposed fastener panels due to their concealed fasteners and more complex installation. Metal shingles or tiles can also vary.
Gauge and Finish: Thicker gauge metal (lower number) costs more. Specialized coatings and finishes (e.g., Kynar 500) add to the price but offer enhanced durability and aesthetics.
Roof Complexity: Roofs with multiple valleys, hips, dormers, skylights, or steep pitches require more labor, custom cuts, and specialized flashing, increasing costs.
Labor Rates: Installation costs vary by geographic location and the experience of the roofing contractor.
Underlayment: High-quality synthetic underlayments or ice-and-water shield membranes will add to the material cost but provide superior protection.
Old Roof Removal: If an existing roof needs to be torn off, this will add to the labor and disposal costs.
Benefits of Metal Roofing
Despite the initial investment, metal roofs offer numerous long-term advantages:
Longevity: Metal roofs can last 40-70 years or more, significantly outperforming asphalt shingles.
Durability: They are highly resistant to wind, fire, rot, mildew, and pests.
Energy Efficiency: Many metal roofs are ENERGY STAR® rated, reflecting solar radiant heat and reducing cooling costs.
Low Maintenance: Generally require less maintenance than other roofing materials.
Sustainability: Often made from recycled content and are 100% recyclable at the end of their life.
Example Calculation
Let's consider a roof that is 40 feet long and 25 feet wide with a 6/12 pitch. Using the default values in the calculator:
Roof Length: 40 ft
Roof Width: 25 ft
Roof Rise: 6 inches
Roof Run: 12 inches
Metal Panel Cost per Sq Ft: $5.00
Labor Cost per Sq Ft: $6.00
Underlayment Cost per Sq Ft: $1.00
Fastener & Trim Cost per Sq Ft: $1.50
Waste Factor: 10%
The calculator would first determine the roof's actual surface area, accounting for the pitch, and then apply the per-square-foot costs for materials, labor, underlayment, and accessories, plus the waste factor, to provide a comprehensive cost estimate.
Disclaimer: This calculator provides an estimate for budgeting purposes only. Actual costs may vary based on specific material choices, contractor quotes, regional pricing, and unforeseen project complexities. Always obtain multiple detailed quotes from qualified local roofing professionals for an accurate project cost.