I assumed the poster was not counting the locked drawer as a row...otherwise there would be no need to "add". So it's 4x5 "floating" icons, plus 4 "drawer" icons, but you can't change the layout as far as I know anyway.
EDIT: Wow, I'll be damned! That is weird since I've seen a bunch of pics with only 4x5 plus 4x1 on an iPhone 6, don't know if those were faked or what.