DIY Fitting Stair Carpet

Measure the width and length of your stairway, using a tape measure. The carpet width should be 4 inches wider than your tackless strips. To have an idea of the needed tackless strip width, measure the width of your carpet runner and deduct 4 inches from the total carpet width. Mark this length on all the risers with a pen marker.

Cut the tackless strips so they are 4 inches shorter than the total width of your carpet, using a utility knife. Put the carpet runner upside-down, and run a chalk line on two sides so that the distance between the chalk lines is equal to the width of the tackless strip.

Install the tackless strips starting from the bottom of the stairway. Position the front tackless strip 1/2 inch from and parallel to the corner between the tread and the riser. Usually two tackless strips are required for each tread; one for the front and the other for the back on the tread. Place another tackless strip at the back of the tread, 1/2 inch from its edge. The printed arrows on the strips should point toward the top of your stairway.

Hammer down the tackless strips with the pre-installed nails that come with the strips to each of the treads. Work the instructions from Step 3 to Step 4 until you've installed tackless strips the entire length of your stairway.

Cut carpet padding the same width as the strips, using the utility knife. Wrap the padding around the front edge of the steps while leaving some slack.

Roll out the length of carpet, right side up, from the top of your stairway and let it free-fall to the bottom of the stairs. Center it by adjusting the carpet on the stairway, using the chalk lines on the underside of the carpet as guide.

Work from the bottom of your stairway toward the top. Use a straight edge to fold the back of the carpet along the chalk lines, covering the carpet padding. Push the carpet onto the tack strips, using an awl. Check that the carpet edges are straight.

Staple the carpet onto the padding on each riser 1/4 inch below the tread, leaving 3 inches between the staples. Push tight the carpet into the corner of the riser and tread with a knee kicker once you finish stapling the carpet to each riser. Secure the ends and edges of the carpet with a few carpet tacks.