Q. Is the keriah done on the lapel of a jacket a proper rent?

A. Although it is a common tradition to tear only the lapel of a jacket even when mourning for parents, some Poskim maintain that a lapel is not regarded as the “begged” (garment) proper even when used to cover ones neck and chest in cold weather. (Zichron Eliahu quoted in Mourning in Halacha p. 94)

Horav Shlomo Miller’s Shlit”a opinion is that on the onset (lekatchila) the rent should go over to the jacket itself, specially when done for parents avelus, when the requirement of “megaleh livo” (uncovering the heart) applies.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a