Solid Wood Interior Door SOLID WOOD: Our custom interior wood doors are crafted from wood ONLY. The most popular wood options include Mahogany, Cherry, Knotty Alder, Walnut, Ash, Oak or any other wood species of your choice. Each wood slab is 1-3/4" thick, is pre-finished with a furniture quality wood finish, and comes with a knock down jamb, and 4" x 4" square corners hinges.