You would get 50% pieds and the rest would be split pied. If you breed her to another pied you will get all pieds. As for heavy pied and light pied I can't help. I never got into breeding for patterns.
Yes you will need to get a pied male, the heavier pied he is the better the chances of you getting heavy pied chicks are. If you get split pied or light pied male the chances of a heavy pied is small, not impossible but unlikely