I am also am a firm believer in never limiting water.. I ALWAYS have clean fresh bottled water avalible 24/7. I also wash her dish everytime I refresh it. 3 to 4 times a day.. I hate the taste of stale water, so I KNOW Taycie must
I am totally guessing here but If you have carpet maybe she is smelling urine and that is why she goes inside. Dogs can smell urine even when you can't and if she can smell it she it going to go no matter what.
I would also have her checked, your vet could rule out a possible cause for a UTI, this will also ease your mind if you are having concerns.