Yes they make them super big and that is the size I would recommend. Along with saving the backs and knees, it will also save the balls, and whatever hard flooring you might have. It will also quiet the room down quite a bit.If you have a ball go off the table, chances are it is going to land well beyond the size of your rug, unless you have a rug that is quite a bit larger than your table, IMHO.
Did an area rug in the basement then got matching carpet tiles later to put down around the parameter. Some heavy duty carpet tape and they haven’t movedOld thread, but resurrected! I put 2’ carpet tiles around the perimeter. When I first put them in they fit nice and tight, then the dog did some hot laps around the table and I had to redo them with some border strips.
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