I was contacted by a family member who wants to redo some flooring in a portion of their house. The flooring that is currently in place is linoleum that has seen better days. The linoleum was installed on 1/4″ mahogany underlayment sheeting that was nailed on a 6″ grid with the adhesive coated nails which is on top of plywood. She (family member) is wanting to install some type of wood flooring whether it is floating or nailed down has not been decided. When I was asked about this project and whether the linoleum should be removed my first reaction was “of course not, install it over the linoleum.” Then I recalled replacing a French door that had less than a 1/4″ of spacing between the topside of the jamb and the bottom of the header, it was a really snug fit. Remembering that I had seen this I realized that if one was to install flooring on top of the linoleum then there would be a need for a 1/2″ transition down to the threshold of the French door, which would look awful. Although if I removed the linoleum it would give me an additional 1/8″ or so, but would the benefit be worth the effort? In my mind for this to look normal I would have to raise the door, which means either trim the header or raise the header. With this being said I wonder if anyone knows, has seen, or could imagine a possible transition from the future finished floor height to the threshold enabling me to leave the door in the current position. Thoughts or suggestions?