Bellawood Prefinished Solid Wood Hickory 5/8 in. Thick x 11.5 in. Wide x 48 in. Length Retrofit Stair Tread, $89.99 USD/Box, LL Flooring (Lumber Liquidators)

Install these treads on top of existing steps for a quick upgrade. They measure 5/8 inch thick, 11.5 inches wide, and 48 inches long, and offer a durable, solid wood surface for retrofitting stairs at $89.99 per box.