Locate the upper seam of the carpet, which is usually under the stair nosing at the top of the stairs. Remove the tacks or nails holding it in place. Grasp the carpet firmly and pull it down the stairs, exposing tack strips, nails or tacks that you need to pull out as you go. Remove tack strips with a claw hammer. Roll the carpet and set it aside.
Scrape off the residual adhesive backing on the stair treads and risers with the edge of a putty knife. Scrub the stairs with a soapy solution and a brush and wipe off the surface with a wet rag. Allow the stairs to dry thoroughly.
Measure the depth and width of the topmost stair’s tread and riser. Divide the depth of the tread by the width of a plank to determine the number of hardwood planks you need to cover the tread. Also divide the height of the riser by the width of a plank to determine the number of planks you need to cover the risers.
Cut hardwood planks to the required width and depth for the stair using a circular saw. Also cut the ledge, or bullnose, for each stair using a circular saw, ensuring it falls flush with the edge of the riser directly underneath. Measure the width of the bullnose so you know how much gap to leave on the stair tread for its installation.
Walk to the bottom of the stairs. Cut off the tongue of a hardwood flooring plank for the lowermost riser. Apply flooring adhesive over the back of this hardwood plank. Set this plank on the bottom of the riser and tap it in place gently with a rubber mallet.
Spread adhesive over the grooved side of the plank. Also spread glue over the back of another plank, and slide its tongue into the glued groove of the board directly below. Tap the joint lightly to help the adhesive set. Repeat the process of installing boards until you cover the riser.
Cover stair treads with hardwood planks. Apply a bead of glue to the back of a hardwood floor plank and set it on the tread, with its grooved side flush against the corner of the riser for the step above. Tap it gently so it falls flush with the wall.
Spread glue over the grooved end and back of another plank. Fit this plank on the tread, joining its glued grooved side into the tongue of the plank already installed. Tap the plank in place and repeat the process of installing the planks until a small gap remains for the bullnose.
Apply glue into the grooved end and back of the bullnose. Slide the grooved section into the tongue of the last plank and tap the joint. Repeat this process for installing hardwood planks on the stairs.