Step 7 · Reinforce for Maximum Stability (Optional but Recommended)

To provide extra stability, consider securing the new tread with screws or finish nails. If you can access the underside of the stairs, drive fasteners up into the tread. If working from the top, use a countersink bit to create pilot holes, drive your screws, and then fill the small holes with a matching wood putty for a clean, hidden finish.