Is this legal to do on a house?

I moved from my old house into my new house but I still own the old house. Right now I am currently renting out the house to someone, so I have people living there at the moment. Here's the thing at my old house we have a pretty big concrete patio area and I was wondering if it would be legal to take away half of the patio stones to use for my new house, or do I have to wait till the people move out?