Stair Carpet Calculator

Measure tread depth (front to back including nosing), riser height (vertical part), and stair width. For each step, the carpet needed per step = (tread depth + riser height + 1 inch for wrapping) × stair width. Multiply by the number of steps. Add 3-4 extra inches for the top nosing and bottom finishing. Also measure the landing area (if any). Always add 10-15% waste for pattern matching, seams, and trimming. Professional installers typically add 18 inches extra for waste and matching.

Average cost to carpet stairs: $150-400 for a standard straight staircase (12-14 steps). This breaks down to $10-30 per step. Material: $3-10 per sq ft for carpet, $1-3 per sq ft for padding. Labor: $8-15 per step for installation. Total range: Basic carpet: $150-250, Mid-grade: $250-400, Premium: $400-700+. Curved or winding stairs cost 50-100% more due to complex cutting and fitting. Landings add $50-150 each. Remove old carpet: $25-50 for stairs.

For a standard staircase with 14 steps, 36 inches wide, 10-inch tread, 7.5-inch riser: Per step = (10 + 1 nosing + 7.5 riser + 1 wrapping) × 36 inches = 19.5 × 36 = 702 sq inches. Total = 14 × 702 = 9,828 sq inches ÷ 1,296 = 7.6 sq ft ÷ 9 = 0.84 sq yd per step × 14 = 11.8 sq yd total with waste. A standard 12-ft wide carpet roll typically wastes more, especially if the stair width is less than 12 ft. Always consult your installer for final measurements.

Yes, using the same carpet throughout creates a seamless look. However, stairs experience much more wear than bedrooms, so choose a durable carpet grade. Recommended for stairs: Nylon or polyester with face weight of 40-50 oz/sq yd, dense twist (5+ twists per inch), 1/2-inch thick padding (density 6-8 lbs). Berber or loop pile carpets are not recommended for stairs — loops catch and pull easily. Frieze or textured saxony carpets work well. Darker colors and patterns hide dirt better on high-traffic stairs.