I am installing a used pedistal sink onto concrete foundation and need some advise on the pedistal. Before I tile the floor I need to install the pedistal. Is it nesisary for me to bolt the pedistal to the floor? And second how can I tell how far from the wall it should be located? (Should I just set the sink on top of it and make sure it is touching the wall? or is there more to it than that?)