Sleep walking is very common issue. In your case there is nothing to worry about. Sleeping in your living room is very safe. Sometimes people even leave their houses or drive car while sleeping.
I think you should tell your family so that they don't wake you up if they find you sleep walking. Sometime sleep walkers might get angry and even hurt the person who tries to wake them up. The best thing is that family members should gently take the sleep walker back to bed while holding their hand.