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The Flooring Calculator adds the length × width of up to three rooms plus closets and nooks, then adds the waste allowance the flooring maker publishes. Pergo's Installation Essentials Guide says to add 10% to the square footage for standard laminate installations and 15% for diagonal ones; Shaw's solid hardwood installation instructions require a 5–10% waste factor depending on layout, and more for diagonal, herringbone or bordered floors. The total is divided by the square feet in a carton and rounded up, and priced at your cost per square foot. The calculator also measures the room perimeter less doorways for baseboard or quarter round, which hides the expansion gap: 3/8 in for Pergo laminate and 3/4 in for Shaw solid hardwood. Acclimate unopened cartons in the room for at least 48 hours for Pergo, 72 for Shaw. A 12 × 15 ft room is 180 sq ft: 198 sq ft with 10% laminate waste, 10 cartons of 20 sq ft and 51 ft of trim.
Pergo's laminate installation guide: add 10% to the square footage for standard installations and 15% for diagonal; leave a 3/8 in expansion space round the perimeter; acclimate unopened cartons at least 48 hours. Shaw's solid hardwood instructions: a 5–10% waste factor depending on layout, more for diagonal, herringbone or bordered floors; at least 3/4 in expansion space at walls; 72 hours minimum acclimation.
| Room | Area | Laminate, straight lay (Pergo +10%) | Laminate, diagonal (Pergo +15%) | Solid hardwood, simple room (Shaw +5%) | Solid hardwood, cut-up layout (Shaw +10%) |
|---|---|---|---|---|---|
| 10 × 10 ft | 100 sq ft | 110 | 115 | 105 | 110 |
| 10 × 12 ft | 120 sq ft | 132 | 138 | 126 | 132 |
| 12 × 12 ft | 144 sq ft | 158.4 | 165.6 | 151.2 | 158.4 |
| 12 × 15 ft | 180 sq ft | 198 | 207 | 189 | 198 |
| 14 × 16 ft | 224 sq ft | 246.4 | 257.6 | 235.2 | 246.4 |
| 16 × 20 ft | 320 sq ft | 352 | 368 | 336 | 352 |
| 20 × 24 ft | 480 sq ft | 528 | 552 | 504 | 528 |
Multiply each room's length by its width, add closets and nooks, then add the waste allowance for your floor and layout and divide by the square feet in a carton, rounding up. A 12 × 15 ft room is 180 sq ft; with Pergo's 10% that is 198 sq ft, or 10 cartons of 20 sq ft.
Pergo's installation guide says to add 10% to your square footage for standard installations and 15% for diagonal installations.
Shaw's solid hardwood installation instructions require a 5–10% waste factor depending on the layout, and a higher percentage for diagonal, herringbone or bordered installations.
Pergo laminate needs a 3/8 in expansion space round the whole perimeter. Shaw solid hardwood needs at least 3/4 in at all walls and vertical obstructions. Baseboard and quarter round cover the gap, so measure the room perimeter for trim.
Pergo says to lay unopened cartons flat in the room for at least 48 hours, or 96 hours in very dry or very humid climates. Shaw requires at least 72 hours on site for solid hardwood.
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