We have a garage that was converted into a bedroom and a hall to the basement. This room is very hot in the summer and cold in the winter. I was able to drill a hole and found no insulation between the concrete floor of the old garage and the new addition wood floor. the space between the two is about 12". Their is a main beam running down the center of the converted room and the joists run off of that. How can I add insulation to this room without ripping up all the hardwood flooring?