It's warmer with wood. Solid hardwood flooring, like all solid wood, is a natural insulator. It's made of microscopic hollow cells and these air spaces produce high insulating values. It would take 15 inches of concrete to equal the insulating qualities of just one inch of wood. Grades of oak.
Appearance alone determines the grade of each hardwood flooring piece.
All grades are equally strong and serviceable in any application. Oak's low cost. Whatever choices you make in selecting your solid hardwood flooring, the cost over the years generally will be less than the cost of quality carpeting. Even vinyl tile will only last an estimated 20 year. On the other hand, solid hardwood flooring will last for the life of the building and can be refinished five to 10 or more times, depending on flooring conditions.