Standard sheet sizes: 4×8 ft (32 ft²) for residential, 4×10 ft (40 ft²) for tall residential or commercial walls, 4×12 ft (48 ft²) for commercial taping efficiency. Pick a size based on installer preference and wall height.
Formula: sheets = ceil((wall area − openings) × (1 + waste/100) ÷ sheet area). Waste defaults to 10% for typical residential rooms, 12-15% for cut-up bathrooms or vaulted ceilings, 8% for large simple commercial spaces.
Multiple sheet types on the same job (Type X fire-rated, moisture-resistant, sound-attenuating) need separate sheet-count tracking since each type has a different unit cost and is ordered separately from the supplier.