absolutely no! this is a matter of attitude instead of issue. You need to make it very clear that not asking is wrong no matter of hygiene or not. If she respect you , she need to ask, right?!
depends on your maid personality and usual performance, then u need to give her the warning and make it for the rules in the house. I have a bad maid, so I will be very strict in future (..waiting for the new maid to come..)