The dining room set still looks good; the wood is fine and the chairs don't squeak, but the seat fabric is a bit outdated and drab. Changing these covers will update the set, and with accurate measuring, you can purchase the correct amount of fabric with confidence.
Measure the Seats
Measure the width (side to side) and depth (front to back) of the seats at the widest and deepest part. To these measurements, add 6 inches on each side and 6 inches on the front and back. Mark the measurements on the fabric with a fabric pen or chalk so that you will know where to cut. Write the measurements down, and use them for the other chairs if you prefer not to measure each chair separately. Measurements are written as width by length.
Another method to cut fabric for your six chairs is to use a template. Cut a piece of clear plastic using the measurements you prepared for the first chair. Place it on your fabric, draw around it with chalk or a fabric pen and cut on the lines. Use the plastic piece as a template for the other chairs.
Measure the long edge of the fabric from the beginning of the first to the outside edge of the last tracing of the pattern, which is the fabric required for all six seats. Divide this number of inches by 36 for the number of yards required, and round up to the nearest half-yard. For example, if the piece of fabric required is 89 inches long, divide this by 36 to equal 2.47; round up to 2 1/2 yards.
Fabric Requirement Generalization
Most upholstery and tapestry fabric is 54 inches wide and will have a pattern repeating twice across the width. Most dining room chairs can be covered using a piece of fabric 27 x 27 inches; therefore, plan to use a piece of fabric 27 inches long by 54 inches wide, or about three-quarters of a yard for two chair seats, which does not allow for pattern placement matching but is a general rule.