Southwind's right, but here's a bit more info...
The answer to your question is "Kinda."
We have 10 holidays/year. For half, you can either take double time for the day, and be done, or take straight time for the day, and get a different (paid) day off somewhere else. For the other "non-premium" holidays, DT isn't an option, but floating the holiday elsewhere is.
So, as Southwind notes, in theory, you could string 5 of them together at some point for a de facto extra week.
Make sense?