Our basement floor is poured concrete either directly onto bedrock or in some areas up to 3" of gravel over the concrete. The bedrock goes out under the footings on the front edge of the room directly to the outside with no covering on the bedrock outside the wall. Obviously it gets quite cold in the winter. We would like to use the area which is 18' X 24' as a games room and are thinking about a carpeted floor with some ceramic borders and fireplace hearth. Can you provide any tips and/or suggestions. Thank you.