The floors of the second floor of my house are 2 1/4 inch wide red oak strips. I want to install wood flooring on the ground floor, too. The house is slab on grade, so I can't use the same 3/4" thick oak I used upstairs. I'm interested in ideas for using two different product types upstairs and down. As well, I am interested in thoughts on using two different species of wood on each floor. The stairs are red oak.