How to Refinish Stairs & Banisters

Use your power sander and 36-grit sandpaper to sand the banister and each of the stairs. Sand them until the old finish is completely off.

Reload the sander with 80-grit sandpaper and repeat the process to completely smooth out the wood surfaces. Vacuum well.

Brush wood stain over the banister starting at the top. Working in sections, cover the wood with stain, brushing in the direction of the grain. Let it soak in for one minute, then wipe up the excess with old cloths. Do the whole banister.

Brush wood stain onto the top stair in the same manner, brushing it on thickly, letting it sit, then wiping it off.

Skip the next stair, then repeat the staining process on the stair below that. Repeat for every other stair, so each alternate stair is unstained. Let the stained stairs dry overnight. Use only the unstained stairs during the drying time.

Repeat the staining process on the remaining stairs the next day, in the same manner. Let them dry overnight.

Apply polyurethane to the banister with a paintbrush in a thin, even coat, starting at the top and working your way down over the whole piece.

Apply polyurethane to the top stair in the same manner, keeping it thin and smooth. Repeat for each alternate stair.

Let the polyurethane dry for 12 hours. Sand it lightly with 220-grit sandpaper (on both the banister and the stairs), getting it slightly dull. Wipe up the dust. Brush on a second layer, again keeping it on just every alternate stair. Let it dry, hand-sand it and apply a third layer. Let it dry.

Repeat the process of applying polyurethane for the alternate steps, brushing it on in layers, letting them dry, sanding and reapplying.