How to Add a Runner to Stairs & Hallways

Measure the width of the stairs and the width of the runner. Subtract the width of the runner from the width of the stairs and divide the result by two. Mark that distance from the outside of each side of the stairs on each tread, creating layout marks for the runner. Nail a piece of tackless strip -- a piece of metal with pins sticking out of one side used to lay carpet -- measuring 2 inches less than the width of your desired runner in the middle of each tread where it meets the riser. Ensure that the pins point toward the riser.

Cut a piece of carpet padding the same width as the tackless strip and 3 inches deeper than the treads of the stairs. Apply staples linearly every 3 inches to secure the pad to the stair with the edge of the pad lining up with the edge of the tread. Pull the pad tight and secure it to the nosing -- the part of the step that juts from the tread over the riser -- and riser using staples every 3 inches as before. Repeat for each stair.

Attach the runner to the first riser by lining up the edge of the runner with the bottom of the riser and verifying that the runner falls between the layout marks. Secure the runner to the riser, adding a staple linearly every 3 inches.

Smooth the runner up to the tread of that first step, using the knee kicker -- a metal carpet-stretching tool that has a place where you kick it with your upper leg, while on all fours to stretch and smooth the textile and remove any lumps in the runner. Press your knee to the back of the knee kicker, hold down the front knob of the tool with one hand, and use the other hand to keep the tool level. Kick the knee kicker with your knee to force the runner to engage with the tackless strip tautly.

Use the carpet tool and mallet to pack the runner tightly to the crease of the tread and riser. Place a staple where the runner meets the crease between the tread and the riser on either side of the tackless strip already installed there.

Repeat Steps 4 and 5 up the stairs until you get to the end. Cut the runner when you get to the top of the last riser, and dab the edges with glue. Allow the glue to dry completely. Staple the end of the runner along the tip of the riser, putting a staple in every 3 inches.