How to Calculate Yardage for Reupholstering a Sofa

Measure length and width of the inside back of the sofa in inches. The inside back is on the same side as the seat cushion. Multiply the length times the width to get the area of this section.

Measure the length and width of the outside back of the sofa. This is the side opposite the seat cushions. Multiply the measurements to find the area of this section.

Measure the length and width of the outside arm of both sides of the sofa. The outside arm is the flat part of the sofa underneath each arm rest on the outer part of the couch (away from the seat cushions). Multiply the measurements for the area of each outside arm.

Measure the length and width of each inside arm on both sides of the sofa. The width of the inside arms is the distance from the back of the sofa (on the same side as the cushions) to the tips of the arm rests. The length of the inside arms extends from the bottom of each inside arm near the cushion to the outer edge of each arm rest. Multiply length and width for area.

Measure the total length and width of the seat cushions. The width is measured from inside arm to inside arm, plus the amount of material on each side of every cushion. Also add the width from inside arm to inside arm once more to account for the material on the undersides of the cushions. The length is measured from the back to the front of the cushions, plus the material on the back and front sides of each cushion. Again, multiply these measurements to find the area of the seat cushions.

Measure the front gusset's length and width. This is the flat section of the sofa that is facing outward and located below the seat cushions. Figure the area of this section.

Measure the length and width of the arm fronts. This is the strip on each arm that faces outward, in the same direction as the gusset. Find the area of this section as well.

Add up the areas for each section of the couch and divide your total by 36 to figure how many yards of fabric you will need. Add an extra 2.5 inches per seam, as well as extra yardage if you are going to add a skirt or if you have a large pattern that needs to be matched between sections of fabric. Most sofas require a total of between 10 and 15 yards of fabric.