Cottage Roof Calculator – Loan calculator

Cottage Roof Area & Cost Calculator

Use this calculator to estimate the surface area, linear trim requirements, and overall cost for a simple gable roof on your cottage. Accurate measurements are crucial for precise estimates.

Cottage Length (along ridge, in feet):
Cottage Width (perpendicular to ridge, in feet):
Roof Pitch (in degrees, e.g., 30-45):
Eave Overhang (horizontal projection, in feet):
Gable Overhang (horizontal projection, in feet):
Material Waste Percentage (e.g., 10 for 10%):
Roofing Material Cost ($ per sq ft):
Trim/Fascia Material Cost ($ per linear ft):
Labor Cost ($ per sq ft of roof area):

function calculateRoof() { // Get input values var cottageLength = parseFloat(document.getElementById('cottageLength').value); var cottageWidth = parseFloat(document.getElementById('cottageWidth').value); var roofPitchDegrees = parseFloat(document.getElementById('roofPitchDegrees').value); var eaveOverhang = parseFloat(document.getElementById('eaveOverhang').value); var gableOverhang = parseFloat(document.getElementById('gableOverhang').value); var materialWastePercentage = parseFloat(document.getElementById('materialWastePercentage').value); var costPerSqFtMaterial = parseFloat(document.getElementById('costPerSqFtMaterial').value); var costPerLinearFtTrim = parseFloat(document.getElementById('costPerLinearFtTrim').value); var costPerSqFtLabor = parseFloat(document.getElementById('costPerSqFtLabor').value); // Input validation if (isNaN(cottageLength) || cottageLength <= 0 || isNaN(cottageWidth) || cottageWidth <= 0 || isNaN(roofPitchDegrees) || roofPitchDegrees 85 || isNaN(eaveOverhang) || eaveOverhang < 0 || isNaN(gableOverhang) || gableOverhang < 0 || isNaN(materialWastePercentage) || materialWastePercentage < 0 || isNaN(costPerSqFtMaterial) || costPerSqFtMaterial < 0 || isNaN(costPerLinearFtTrim) || costPerLinearFtTrim < 0 || isNaN(costPerSqFtLabor) || costPerSqFtLabor < 0) { document.getElementById('result').innerHTML = 'Please enter valid positive numbers for all fields. Roof pitch must be between 5 and 85 degrees.'; return; } // Calculations var pitchRadians = roofPitchDegrees * (Math.PI / 180); // Half width of the cottage var halfCottageWidth = cottageWidth / 2; // Total horizontal run from center to eave edge (including eave overhang) var totalHorizontalRun = halfCottageWidth + eaveOverhang; // Total sloped length from eave edge to ridge var totalSlantLength = totalHorizontalRun / Math.cos(pitchRadians); // Effective length of the roof planes (including gable overhangs) var effectiveRoofPlaneLength = cottageLength + (2 * gableOverhang); // Total Roof Surface Area (two planes) var totalRoofArea = 2 * effectiveRoofPlaneLength * totalSlantLength; // Linear Feet for Trim/Accessories var ridgeLength = cottageLength; // Actual ridge length var eaveLinearFeet = 2 * (cottageLength + (2 * gableOverhang)); // Two eaves, extended by gable overhangs var rakeLinearFeet = 2 * totalSlantLength; // Two rake edges, one on each gable end var totalTrimLinearFeet = ridgeLength + eaveLinearFeet + rakeLinearFeet; // Material Waste Factor var wasteFactor = 1 + (materialWastePercentage / 100); // Estimated Costs var materialCost = totalRoofArea * wasteFactor * costPerSqFtMaterial; var trimCost = totalTrimLinearFeet * costPerLinearFtTrim; var laborCost = totalRoofArea * costPerSqFtLabor; var totalProjectCost = materialCost + trimCost + laborCost; // Display results var resultsHtml = '

Estimated Roof Details:

'; resultsHtml += 'Total Roof Surface Area: ' + totalRoofArea.toFixed(2) + ' sq ft'; resultsHtml += 'Ridge Length: ' + ridgeLength.toFixed(2) + ' linear ft'; resultsHtml += 'Eave Length (total): ' + eaveLinearFeet.toFixed(2) + ' linear ft'; resultsHtml += 'Rake Length (total): ' + rakeLinearFeet.toFixed(2) + ' linear ft'; resultsHtml += 'Total Linear Feet for Trim/Accessories: ' + totalTrimLinearFeet.toFixed(2) + ' linear ft'; resultsHtml += '

Estimated Costs:

'; resultsHtml += 'Estimated Roofing Material Cost: $' + materialCost.toFixed(2) + "; resultsHtml += 'Estimated Trim/Fascia Material Cost: $' + trimCost.toFixed(2) + "; resultsHtml += 'Estimated Labor Cost: $' + laborCost.toFixed(2) + "; resultsHtml += 'Total Estimated Project Cost: $' + totalProjectCost.toFixed(2) + "; document.getElementById('result').innerHTML = resultsHtml; } .calculator-container { background-color: #f9f9f9; border: 1px solid #ddd; padding: 20px; border-radius: 8px; max-width: 600px; margin: 20px auto; font-family: Arial, sans-serif; } .calculator-container h2 { color: #333; text-align: center; margin-bottom: 20px; } .calculator-container p { color: #555; line-height: 1.6; } .calculator-inputs label { display: block; margin-bottom: 5px; font-weight: bold; color: #444; } .calculator-inputs input[type="number"] { width: calc(100% – 22px); padding: 10px; margin-bottom: 15px; border: 1px solid #ccc; border-radius: 4px; box-sizing: border-box; } .calculator-inputs button { background-color: #28a745; color: white; padding: 12px 20px; border: none; border-radius: 4px; cursor: pointer; font-size: 16px; width: 100%; margin-top: 10px; } .calculator-inputs button:hover { background-color: #218838; } .calculator-results { margin-top: 25px; padding: 15px; background-color: #e9f7ef; border: 1px solid #c3e6cb; border-radius: 4px; } .calculator-results h3 { color: #28a745; margin-top: 0; margin-bottom: 10px; } .calculator-results p { margin-bottom: 8px; color: #333; } .calculator-results p strong { color: #000; }

Understanding Your Cottage Roof: Area and Cost Estimation

A cottage roof is a defining feature, offering both protection and aesthetic charm. Whether you're planning a new build, a renovation, or simply need to budget for future maintenance, accurately estimating your roof's area and associated costs is a critical first step. Our Cottage Roof Area & Cost Calculator is designed to provide you with precise figures for a standard gable roof, helping you plan your project effectively.

Why Calculate Your Cottage Roof?

Material Procurement: Knowing the exact square footage helps you purchase the right amount of roofing materials (shingles, underlayment, etc.), minimizing waste and avoiding costly re-orders.
Budgeting: Get a clear estimate of material and labor costs, allowing you to set a realistic budget and avoid financial surprises.
Labor Estimation: Contractors often bid based on roof square footage. Having this number beforehand gives you a benchmark for evaluating quotes.
Accessory Planning: Beyond the main roofing material, you'll need trim, fascia, soffit, and ridge caps. Calculating linear feet helps you budget for these essential components.

How the Calculator Works: Key Inputs Explained

Our calculator uses several key dimensions and cost factors to provide a comprehensive estimate:

Cottage Length (along ridge): This is the measurement of your cottage along the longest horizontal line of the roof, typically where the ridge cap would sit.
Cottage Width (perpendicular to ridge): This is the measurement of your cottage from eave to eave, perpendicular to the ridge line.
Roof Pitch (in degrees): The pitch is the angle of your roof's slope. It's crucial for determining the actual surface area. Common cottage pitches range from 30 to 45 degrees. You can often find this by measuring the rise over run (e.g., 6/12 pitch is about 26.5 degrees, 12/12 is 45 degrees).
Eave Overhang (horizontal projection): This is the horizontal distance your roof extends beyond the exterior wall at the eaves (the lower edges).
Gable Overhang (horizontal projection): This is the horizontal distance your roof extends beyond the exterior wall at the gable ends (the triangular walls).
Material Waste Percentage: Roofing projects inevitably involve some material waste due to cuts, errors, and damaged pieces. A typical waste factor is 10-15%, but it can vary.
Roofing Material Cost ($ per sq ft): Enter the estimated cost per square foot for your chosen roofing material (e.g., asphalt shingles, metal roofing, cedar shakes).
Trim/Fascia Material Cost ($ per linear ft): This accounts for the cost of materials like fascia boards, soffit, drip edge, and ridge caps, which are measured by their linear length.
Labor Cost ($ per sq ft of roof area): This is the estimated cost a contractor charges per square foot to install the roofing materials. Labor rates vary significantly by region and complexity.

Understanding the Results

Once you input your details, the calculator will provide the following estimates:

Total Roof Surface Area: The total square footage of your roof's sloped surfaces, including overhangs. This is the primary number for ordering main roofing materials.
Ridge Length: The linear feet of the ridge line, important for ordering ridge caps.
Eave Length (total): The total linear feet of the eave edges, crucial for drip edge, fascia, and soffit.
Rake Length (total): The total linear feet of the sloped edges at the gable ends, also important for drip edge and fascia.
Total Linear Feet for Trim/Accessories: A combined total of all linear measurements needed for various trim components.
Estimated Roofing Material Cost: The projected cost for your primary roofing material, factoring in waste.
Estimated Trim/Fascia Material Cost: The projected cost for all linear trim components.
Estimated Labor Cost: The projected cost for professional installation.
Total Estimated Project Cost: The sum of all material and labor costs, giving you a comprehensive budget figure.

Example Calculation: A Small Cottage Roof

Let's consider a typical scenario for a small cottage:

Cottage Length: 25 feet
Cottage Width: 18 feet
Roof Pitch: 35 degrees
Eave Overhang: 1.25 feet
Gable Overhang: 0.75 feet
Material Waste Percentage: 10%
Roofing Material Cost: $3.50 per sq ft (e.g., architectural shingles)
Trim/Fascia Material Cost: $8.00 per linear ft
Labor Cost: $2.00 per sq ft

Using these inputs, the calculator would yield results similar to:

Total Roof Surface Area: Approximately 1150.00 sq ft
Ridge Length: 25.00 linear ft
Eave Length (total): 56.00 linear ft
Rake Length (total): 35.00 linear ft
Total Linear Feet for Trim/Accessories: 116.00 linear ft
Estimated Roofing Material Cost: $4427.50
Estimated Trim/Fascia Material Cost: $928.00
Estimated Labor Cost: $2300.00
Total Estimated Project Cost: $7655.50

This example demonstrates how the calculator provides a detailed breakdown, allowing you to budget for each aspect of your cottage roofing project. Remember that these are estimates, and actual costs may vary based on local market conditions, specific material choices, and contractor bids.