As far as I know wake turbulences tends to go down with a 500ft/min Vz which means that if the guy in front of you is on the GS and that you follow the same path, you should be 500 ft above its wake when passing a minute after him.
In addition, should you be landing facing the wind (which is generally recommended), the wake should be little bit pushed back thus increasing its clearance from the glide path.
Does this make sense ?