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Flooring Estimators

Carpet Calculator

Estimate broadloom or carpet tiles for any space. Factor in roll width to find the required linear length, or calculate pieces for tile-based flooring with a professional waste allowance.

Carpet Calculator

Broadloom roll goods or carpet tiles with waste allowance

Results

Enter dimensions above to calculate

How Broadloom is Calculated

Broadloom comes in fixed widths. The calculator suggests the best orientation to minimize seams and waste while ensuring the entire room is covered.

ROOM AREA SCRAP / WASTE Roll Width (W) Linear Length (L)

Common Broadloom Roll Widths

System Roll Width Typical Use
Imperial 12 feet Standard residential US
Imperial 15 feet Wide-width commercial
Metric 3.66 metres Standard UK/Aus/NZ
Metric 4.00 metres Standard European

Step-by-Step Formulas

1. Net Floor Area

Net Area = (Length × Width) − Openings

Begin by measuring the total footprint of the room. Subtract any areas that will not be carpeted, such as a fireplace hearth or a built-in cabinetry base.

2. Waste Allowance

Order Area = Net Area × (1 + Waste%)

Waste covers trimming, fitting into doorways, and pattern matching. 10% is standard. For patterned carpet or high-traffic areas where seams must be minimized, budget 12–15%.

3. Broadloom Roll Planning

Roll Length = ceil(Order Area ÷ Roll Width)

Broadloom is sold by the linear foot or yard from a fixed-width roll (usually 12 ft or 4 m). The calculator accounts for total coverage and suggested orientation to minimize waste.

4. Carpet Tile Estimation

Tiles = ceil(Order Area ÷ Tile Area)

For carpet tiles, divide the order area by the individual tile area (eg 500 × 500 mm). The result is rounded up to the nearest whole tile.

Worked Example

Imperial: 15 ft × 20 ft master bedroom, 12 ft roll width, 10% waste.

Net Area = 15 × 20 = 300 ft²
Order Area (+10%) = 300 × 1.10 = 330 ft²
Broadloom runs (across 15') = ceil(15 / 12) = 2 runs
Total linear length = 2 runs × 20 ft = 40 linear feet
Tile alternative (18"×18") = 330 ft² ÷ 2.25 ft² ≈ 147 tiles

💡 Pro tip

Whenever possible, plan seams to be away from doorways and main traffic light sources. For patterned carpet, ensure you order enough to allow for the horizontal and vertical "pattern repeat" length, which can significantly increase waste beyond 10%.

Frequently Asked Questions

How much waste should I add for carpet?
For most rooms, 10% waste is standard. Add 15% if the room is irregular or if you are using patterned carpet that requires precise seam alignment.
What is the standard broadloom roll width?
The most common width is 12 feet (3.66 m), but 15-foot and 4-metre rolls are also widely available. Always confirm the roll width with your retailer.
Should I buy carpet by square feet or square yards?
Suppliers traditionally quote by the square yard, but modern retailers often use square feet. Note: 1 sq yd = 9 sq ft.

Assumptions & Reference Values

This tool returns estimates using the standard engineering formulas and the default waste/coverage/density/yield parameters shown in the calculator inputs and results. Always verify assumptions (material specs, site conditions, and local requirements) against your supplier data and project plans.

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