I want to use this for the floor in my home gym which is approximately 15 feet by 20 feet. Do these rolls need to be glued to the floor? Can they just be placed on top? Direct over concrete? Do I have to glue them down? Do you recommend going right up to baseboard and using a quarter round molding to keep in position?

You do not have to glue our 3/8" Heavy Duty Rubber Rolls. You can loose lay them in most residential uses. If there is some movement, you can always put some double-sided tape under the rolls or our 5900 Series adhesive if necessary. We do recommend leaving a 1/4" gap between the flooring and the baseboard to account for any expansion or contraction that may occur. To help cover up this gapping, we recommend installing a quarter round around the perimeter to give your floor that finished look.