The bottom is a piece of 3/4” birch plywood that is also finished with Rubio. Plywood was selected as a result of it being hidden under the desk. People really won’t see it unless they are under the desk. The finish looks good. Probably the most obvious thing are the pocket holes. A large number of pocket holes were used to ensure there is enough strength. Pocket holes are not known for their strength, so using a lot of them will only help. Glues was not used in fear of needing to disassemble in the future.
