When you think of hardwood floors, you think of unfinished floors that you have to sand and finish. If you are installing hardwood floors on a concrete slab or have a height problem, use 3/8" materials because they're thinner. Hardwood flooring is increasing in popularity and is one of the most durable choices - especially when choosing a pre-finished hardwood floor to install. DIY Network experts explain the different types of hardwood flooring. Finitec wood floor.