What is the formula to calculate yards of fabric needed to cover a sofa?

To calculate the yards of fabric needed to cover a sofa, you typically use the formula: Total Fabric Needed (in yards) = (Sofa Length (in inches) + Sofa Width (in inches) + Sofa Height (in inches)) / 36. This formula accounts for the total surface area, including cushions and any additional features. It's advisable to add an extra 10-20% for seams, pattern matching, and any mistakes. Always refer to the specific sofa dimensions and design for a more accurate estimate.