Stairs leading directly from a living room or central hallway look more attractive and inviting when carpeted. And, a carpeted stairway will quiet your home by softening footsteps and absorbing sound waves. Carpeted stairs are safer, too, lessening your chances of slipping.
Avoid utility-grade carpeting. Stairways get heavy wear, especially along the tread nosing. Choose an easy-to-clean variety with a dense pile.
Carpet with attached cushion backing is cheaper and easier to install, but isn’t recommended for stairways.
Because you want a long, narrow runner, you may be able to buy remnants of high-quality carpeting at much less than the going rate for a room-size piece. The runner need not be one length; seams can be hidden under the tread nosing.
Remember, the pile on each piece should always lie facing toward the bottom of the stairs. Both ascending and descending, the pressure of your foot is mostly toward the tread nosing, so unless the pile faces the same way, wear will be excessive--perhaps doubled.
Feel pile direction by running your hand lightly across the carpet.
The most common method for carpeting a stairway with a closed wall on one side and open balusters at the other is to roll both edges under.
Allow about 1 inch from the wall with 1 1/4-inch roll-under at the edges. If your carpeting won’t unravel at a cut edge, you can butt it against the sidewall without roll-under.
Determine the total length of the runner by measuring one tread and one riser, wrapping the tape measure around the nosing and holding it against the riser below the tread with your thumb. Add 1 inch to allow for the thickness of the padding under the carpet.
Multiply this figure by the number of steps. Remember to allow extra carpeting if your runner is in two or more sections, because each section must join under a tread nosing.
To get width, measure from the wall to the base of the balusters, or whatever portion of the step you will be covering.
Add 2 1/2 inches for rolling the edges under--1 1/4 inches for each side. Because you will probably need to trim at least one edge along the runner’s length, allow an additional inch for this.
If your carpeting has irregular edges, be sure you have enough material to trim the full length of both sides straight.
Measure a stairway with a landing as if the landing were one deep step. Ideally, cover the landing and the first riser above it with one piece. If you can’t, include the riser with the steps above it.
Winder steps--wedge-shaped steps that turn a corner--require carpeting about 50% wider than a straight runner, and waste considerable material. You need a separate piece for each step and the riser above it. The pile on each tread must be at right angles to the nosing and facing downstairs.
If your stairs have been carpeted, remove old nails or tacks and any quarter-round trim or molding, check treads and risers for looseness, and secure any that need it using glue and 8d finishing nails.
Refinish the parts of the treads and risers that will show before putting down carpeting.