function calculateFlooring() {
// Get Inputs
var length = parseFloat(document.getElementById('room_len').value);
var width = parseFloat(document.getElementById('room_wid').value);
var wastePct = parseFloat(document.getElementById('waste_pct').value);
var price = parseFloat(document.getElementById('price_sqft').value);
var boxSize = parseFloat(document.getElementById('box_size').value);
var errorBox = document.getElementById('error_box');
var resultArea = document.getElementById('result_area');
// Validation
if (isNaN(length) || isNaN(width) || length <= 0 || width 0) {
var totalCost = Math.ceil(totalSqFt) * price;
document.getElementById('res_total_cost').innerHTML = "$" + totalCost.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('cost_section').style.display = 'block';
} else {
document.getElementById('cost_section').style.display = 'none';
}
// Box Calculation
if (!isNaN(boxSize) && boxSize > 0) {
var boxes = Math.ceil(totalSqFt / boxSize);
document.getElementById('res_boxes').innerHTML = boxes;
document.getElementById('box_section').style.display = 'block';
// If we have price and boxes, recalculate cost based on full boxes
if (!isNaN(price) && price > 0) {
var boxCost = boxes * boxSize * price;
document.getElementById('res_total_cost').innerHTML = "$" + boxCost.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
}
} else {
document.getElementById('box_section').style.display = 'none';
}
resultArea.style.display = 'block';
}
How to Calculate Flooring Material Requirements
Whether you are installing hardwood, laminate, vinyl plank, or tile, accurately calculating the square footage needed is the first step to a successful renovation. Buying too little material causes project delays, while buying too much is a waste of budget. This flooring calculator helps you determine the exact coverage needed including standard industry waste factors.
1. Measure Your Room
To determine the Net Square Footage, measure the length and width of the room at its widest points. Multiply these two numbers:
Length (ft) × Width (ft) = Area (sq. ft.).
For example, a 10×12 bedroom is 120 square feet.
2. The Importance of Waste Factor
You should never purchase exactly the net area of the room. Cuts, breakage, and mistakes are inevitable during installation. Professional installers recommend adding a "waste factor" or "overage" percentage to your total:
5% Waste: For simple, square rooms with no obstructions using rolled goods (carpet/vinyl).
10% Waste: The industry standard for hardwood, laminate, and basic tile installations.
15-20% Waste: Required for rooms with complex layouts, many corners, or when installing tile in a diagonal pattern (which requires more cuts).
3. Calculating Boxes Needed
Flooring is typically sold in boxes that cover a specific amount of square footage (e.g., 20.5 sq. ft. per carton). To find out how many boxes to buy, divide your Total Material Needed (Net Area + Waste) by the Square Footage per Box. Always round up to the nearest whole number, as you cannot buy partial boxes.
Tips for Success
When purchasing your flooring, ensure all boxes come from the same "dye lot" or batch number. Slight color variations can occur between batches, which may be noticeable once installed. Having that extra 10% calculated by our tool ensures you have enough matching material to finish the job correctly.