You might find two-tone stairs, with stained treads and painted risers, in small country homes, and the design can make a larger home with hardwood floors and wainscoted walls feel especially elegant. If the stairs are new, the task isn't a difficult one, but you may have your work cut out for you if the stairs are already finished. As with any other painting job, the key to impressive results is meticulous preparation.
Once the stairs are ready, it's best to start by painting the risers. That way, you can remove any paint you get on the treads before staining them; and painted risers are relatively easy to protect from stain. Choose semigloss or gloss paint -- both are easier to keep clean than flat paint. Also, if you use a dark color, you won't find it necessary to clean as often.
Paint the Risers
Preparing stairs for painting is a messy procedure -- especially if you have to strip a finish -- so cover the floors around the staircase with dropcloths. You should also cordon off the staircase -- you don't want anyone walking on your freshly sanded treads.
Remove staples, tacks and nails from stairs that were previously carpeted, using pliers and a flat-head screwdriver. Fill all holes with wood filler.
Strip any previous finish from the treads, using paint stripper. You can also strip the risers, but it's not entirely necessary, because you're going to paint them anyway. You can simply wash them with a solution of 1/2 cup trisodium phosphate and water to clean and etch the existing paint.
Sand the treads with a palm sander and 100-grit sandpaper. Then hand-sand, going with the grain, using 120-grit sandpaper. Hand-sand the risers; even if they have a coat of paint, scuffing them is a good idea, to improve paint adhesion.
Mask around each riser, using painter's tape. Pay special attention to the walls -- if you get paint on the treads, you can always scrape it off prior to staining them.
Paint the risers with a paintbrush, starting at the top or bottom of the staircase, whichever is more convenient. Use long strokes when painting. You'll probably need at least two coats of paint; wait at least 24 hours after the final coat dries before removing the masking tape from the stair treads. Leave the tape on the walls.
Stain and Finish the Treads
You can protect the risers from stain with masking tape, but if you're worried about the tape pulling off paint, use a 10-inch drywall knife to cover each riser while you stain the tread.
Start staining at the top of the staircase and work your way down. If you need to use the staircase while painting is in progress, stain and finish every other tread, and then come back and finish the job when those treads have dried.
Apply the stain with a paintbrush, and wipe off the excess with a rag, going with the grain of the wood. Be sure to stain under the tread nosing -- even if you can't see these areas when standing on the stairs, you can see them from the bottom of the staircase.
Move a 10-inch drywall knife along the edge of the tread as you apply stain and wipe it off, if you choose not to mask. Wipe the knife clean with a rag after you stain each tread.
Let the stain dry overnight -- ensuring that no one walks on the stairs during that time -- and then brush on a coat of clear polyurethane floor finish. Scuff the finish with 220-grit sandpaper when it dries, and apply a second coat.