Waterfall within a waterfall

Is it possible to create a waterfall chart where the sections represent portions of 0 - 100% and then have one of those sections divided into subsections that make-up that component? Almost like a waterfall within a waterfall.

I am trying to break down how time is spent over an eight hour shift with one of those section comprising "lost time". From there I'd like to display the make-up of that lost time over a set of categories.

Can this be done in one chart or would the second part be better off in its own waterfall chart?