How much mash water when using rice hulls?

I just put together a recipe using Beersmith. Having experienced a stuck mash last time, I added a pound of rice hulls. So, I have 12.25 pounds of grain and 1 pound of rice hulls for a total of 13.25 pounds. Beersmith calculated I'd need to mash with 16.56 qts. of water. The math tells me that this is 1.25 qts./lb. based on all 13.25 lbs of grain and rice hulls. Is this right or should I calculate my mash water based only on the actual 12.25 lbs. of grain? That would be 15.3 quarts.

I know the difference isn't much, but I'm curious.

to avoid all this extra math I just add the hulls at the end of the mash and stir it before vorlauf, makes life easier.

from what I've read, rice hulls don't really absorb much water...