why does an outlet need to be grounded
If you are talking only about the outlets, they need to be grounded so your third prong of cords plugged in actually does something. Typically, if you have three wire wiring, all you have to do is screw the bare wire to the body of the receptacle box and then pigtail it onto the base of the receptacle. Source(s):ince it could get expensive replacing every outlet with a gfi outlet you can chain them together. put the gfi on the first outlet on the circuit and the rest will be protected. Its not big risk not having a ground. it took 75+ years for homes to be wired with grounds.