.calculator-wrapper {
max-width: 800px;
margin: 0 auto;
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
line-height: 1.6;
color: #333;
}
.calc-container {
background: #f8f9fa;
padding: 30px;
border-radius: 8px;
box-shadow: 0 4px 6px rgba(0,0,0,0.1);
margin-bottom: 40px;
border: 1px solid #e9ecef;
}
.calc-title {
text-align: center;
color: #2c3e50;
margin-bottom: 25px;
font-size: 24px;
font-weight: 700;
}
.input-group {
margin-bottom: 20px;
}
.input-group label {
display: block;
margin-bottom: 8px;
font-weight: 600;
color: #495057;
}
.input-group input, .input-group select {
width: 100%;
padding: 12px;
border: 1px solid #ced4da;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.calc-btn {
width: 100%;
padding: 15px;
background-color: #e67e22;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
transition: background-color 0.2s;
}
.calc-btn:hover {
background-color: #d35400;
}
#result-box {
margin-top: 25px;
padding: 20px;
background-color: #ffffff;
border-left: 5px solid #e67e22;
display: none;
border-radius: 4px;
}
.result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
padding-bottom: 10px;
border-bottom: 1px solid #eee;
}
.result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.result-label {
font-weight: 600;
}
.result-value {
font-weight: 700;
color: #2c3e50;
}
.final-estimate {
font-size: 24px;
color: #e67e22;
}
.article-content {
margin-top: 50px;
}
.article-content h2 {
color: #2c3e50;
margin-top: 30px;
border-bottom: 2px solid #e67e22;
padding-bottom: 10px;
display: inline-block;
}
.article-content p {
margin-bottom: 15px;
font-size: 17px;
}
.article-content ul {
margin-bottom: 20px;
padding-left: 20px;
}
.article-content li {
margin-bottom: 8px;
}
.info-box {
background: #e8f4f8;
padding: 15px;
border-radius: 5px;
margin: 20px 0;
border-left: 4px solid #3498db;
}
@media (max-width: 600px) {
.calc-container {
padding: 15px;
}
}
function calculateRoofingCost() {
// Get inputs
var areaInput = document.getElementById("roofArea").value;
var pitchMultiplier = parseFloat(document.getElementById("roofPitch").value);
var materialCostPerSqFt = parseFloat(document.getElementById("materialType").value);
var tearOffCostPerSqFt = parseFloat(document.getElementById("tearOff").value);
var difficultyMultiplier = parseFloat(document.getElementById("difficulty").value);
// Validation
if (!areaInput || areaInput <= 0) {
alert("Please enter a valid home footprint area.");
return;
}
var baseArea = parseFloat(areaInput);
// Logic:
// 1. Calculate Actual Roof Surface Area = Base Area * Pitch
// 2. Add Waste Factor (10% standard)
var wasteFactor = 1.10;
var actualRoofArea = baseArea * pitchMultiplier * wasteFactor;
// 3. Calculate Material Cost
// Material cost variable includes the cost of the material itself per sq ft.
var totalMaterialCost = actualRoofArea * materialCostPerSqFt;
// 4. Calculate Labor Cost
// Base labor assumption: $3.00 per sq ft for installation, adjusted by difficulty
var baseLaborRate = 3.50;
var totalLaborCost = actualRoofArea * baseLaborRate * difficultyMultiplier;
// 5. Calculate Tear-off Cost
// Tear off is based on actual roof area (old shingles exist on the slope)
var totalTearOffCost = actualRoofArea * tearOffCostPerSqFt;
// 6. Total
var grandTotal = totalMaterialCost + totalLaborCost + totalTearOffCost;
// Formatting currency
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 0,
maximumFractionDigits: 0,
});
// Display Results
document.getElementById("res-size").innerHTML = Math.round(actualRoofArea).toLocaleString() + " sq. ft.";
document.getElementById("res-material").innerHTML = formatter.format(totalMaterialCost);
document.getElementById("res-labor").innerHTML = formatter.format(totalLaborCost);
document.getElementById("res-tearoff").innerHTML = formatter.format(totalTearOffCost);
document.getElementById("res-total").innerHTML = formatter.format(grandTotal);
// Show result box
document.getElementById("result-box").style.display = "block";
}
Roof Replacement Cost Estimator
Flat / Low Slope (Up to 3:12)
Moderate Slope (4:12 – 8:12)
Steep Slope (9:12 – 12:12)
Very Steep / Complex (12:12+)
Asphalt Shingles (Standard) – $4.50/sq ft
Asphalt Shingles (Architectural) – $6.50/sq ft
Metal Seam (Economy) – $10.00/sq ft
Metal Seam (Premium) – $14.00/sq ft
Clay/Concrete Tile – $16.00/sq ft
Natural Slate – $25.00/sq ft
No, install over existing (Not Recommended)
Yes, 1 Layer ($1.50/sq ft)
Yes, 2 Layers ($2.50/sq ft)
Standard Access (Simple)
Difficult Access (Trees, 2+ Stories)
Complex (Many Valleys/Dormers)
Estimated Roof Size (with Pitch & Waste):
0 sq ft
Material Cost:
0
Labor & Installation:
0
Tear-off & Disposal:
0
Total Estimated Cost:
$0
*Estimates include a 10% waste factor. Prices vary by region.
Understanding Roof Replacement Costs
Replacing a roof is one of the most significant investments a homeowner will make. The cost of a new roof varies drastically depending on the materials used, the size of your home, and the complexity of the roof's design. This calculator provides a detailed estimate by factoring in the "hidden" variables that contractors use, such as roof pitch, waste factors, and tear-off requirements.
Key Factors That Influence Pricing
While the square footage of your home is the starting point, the "footprint" doesn't equal the roof area. A steep roof has significantly more surface area than a flat roof covering the same size house. Here are the main cost drivers:
- Roof Pitch (Slope): Steeper roofs require more safety equipment and labor time, increasing the installation cost. A "walkable" roof (4:12 pitch) is cheaper to install than a steep "non-walkable" roof (12:12 pitch).
- Materials: Asphalt shingles are the most common and affordable option, typically ranging from $4.50 to $7.00 per square foot installed. Metal, tile, and slate offer greater longevity but can cost 3x to 5x more.
- Tear-off: Removing old layers of shingles is labor-intensive and requires disposal fees. While you can sometimes layer new shingles over old ones, stripping the roof to the deck is recommended to inspect for water damage.
Did you know? Roofers measure jobs in "Squares." One Square equals 100 square feet of roof area. If your roof is 2,500 sq. ft., a contractor will say it is "25 Squares."
Calculating Waste Factors
A professional estimate always includes a "waste factor," typically 10% to 15%. This accounts for shingles that must be cut to fit valleys, hips, and ridges. A complex roof with many dormers and valleys will have a higher waste percentage than a simple gable roof.
Average Costs by Material (2024 Estimates)
For a standard 2,000 sq. ft. roof, here is what you might expect to pay nationally:
- 3-Tab Asphalt Shingles: $8,000 – $12,000
- Architectural Shingles: $10,000 – $16,000
- Standing Seam Metal: $20,000 – $35,000
- Clay/Concrete Tile: $25,000 – $45,000
When Should You Replace Your Roof?
Most asphalt shingle roofs last between 15 and 25 years. If you notice curling shingles, granule loss in your gutters, or daylight coming through roof boards in your attic, it is time to use the calculator above and start budgeting for a replacement. Always get at least three quotes from licensed local contractors to ensure a fair price.