How to Make a Wall to Wall Carpet Into a Stair Runner

Measure the width of the stairs. Determine whether the stair runner will cover the entire width of the stairs like carpeting, or just the center, like an area rug.

Determine the number of linear feet of carpeting you will need to install a runner on the entire stairway. Begin at the floor at the bottom of the stairs. Measure from the floor, up the riser of the first stair, around the bullnose edge of the stair, then from the front of the step to the back of the step, to the point it meets the riser to the next stair. Write down the measurement of the first stair.

Measure the remaining stairs, one at a time, using the same method in Step 2. Write down each stair's measurement as you go.

Add the measurements of all the stairs together to determine the length of the stair runner you need to cover the entire staircase.

Multiply the total length of the runner, in inches -- the figure you calculated in Step 4 -- by the width of the stair runner that you determined in Step 1. The answer is the total, in square inches, of the amount of carpeting required for the stair runner. Divide this figure by 144, to convert the figure to square feet. This is the total square footage of carpeting required to install a runner on your particular staircase.

Measure the length and width, in inches, of the piece of wall-to-wall carpeting you will convert into a stair runner. Multiply these two measurements together, to arrive at the total square inches of the wall-to-wall carpet. Divide that figure by 144, to arrive at the total square feet of the wall-to-wall carpeting. If the square footage of the wall-to-wall carpeting is equal to or greater than the square footage of the proposed stair runner, as calculated in Step 5.

Cut the wall-to-wall carpeting into strips that are equal to or slightly wider than the proposed width of the stair runner, as determined in Step 1. Use a utility knife with a razor blade. Lay a ruler along the cutting line and draw the utility along the edge of the ruler to create a straight edged cut.

Attach one end of the stair runner to the riser of the first stair, at floor level. Smooth the carpet over the riser, around the bullnose at the edge of the step, and across the step until it comes into contact with the bottom of the riser to the next stair. Pull the carpet straight up around the bullnose, without fastening it there. Fasten the stair runner to the back of the step where the step meets the riser, and finally, put a fastener on the riser near the step it rises up from. Use carpet tacks or heavy duty staples to secure the carpeting to the steps and risers.