Do school-wide holidays count against personal vacation time? I keep hearing different things from different people and it seems there is no clear policy laid out at my institution regarding the definition of graduate student vacation days; I'm curious how PIs and students handle this issue at other places.  

At your institution, do University-wide holidays (such as "Spring Break" or "Winter Recess / Christmas holiday") count towards a graduate student's two weeks vacation?  I always thought the expectation was just that you should be working most of the time, regardless of what day it is, and that seems reasonable to me as long as students have flexibility to take leave when they want/need to without somebody nagging them about the specifics of when/how much time off.  

However, recently there's been the assertion by certain bean-counting PIs in my department that students should be working 6 days a week (including nights) and only taking 2 weeks of leave in total (including major holidays).  Most people probably work about this much anyway, but being told that it's required leaves a bad taste in my mouth.  If people want to get really specific about the "number" of days worked/not-worked, there should be a more standard definition of what comprises a work day (i.e. 9-5, not 9am-12pm).  Am I way out of line here?
This is not meant to be an official opinion, since obviously the rules depend on the local labor laws.


We should distinguish school holidays—days on which classes are cancelled—from official holidays, on which the university offices are closed.
A graduate student not working on a school holiday would be counted as taking leave; however, when the university is closed, that is not normally expected to be a working day for anyone, and thus students would not use a vacation day in such a case.
Advisors should not have policies in place that expect students to be regularly working six days a week, particularly since that would mean that they are potentially in violation of a whole bunch of labor rules.


Given that information, my personal opinion is that research cannot be done according to a timecard. There will be days when you go into the office and figuratively spin your wheels all day, and there are days where you are firing on all cylinders and getting tons done. In my own group, so long as someone:


is prompt in answering requests, 
attends group functions, 
lets me know if he or she will be out of the office for extended periods, and 
is getting his or her work done,


then I will let that person work in whatever manner is most conducive to getting the job done. That's more important to me than knowing they clocked in 8 hours per workday.