The word быт is translated as way of a life.
I must conlude that it is a synonym of obraz zhizni.
So I must conclude that I can construct the following sentence:
1. He has a very unhealthy way of life. All day he drinks alcohol, he doesn't sleep well, he doesnt exercice = U nego nezdrovyi byt, ...
2. He has a very immoral way of life. He is gambling, etc = Y nego nemorolnyi byt ...
3. He has a very simple way of life in his farm house = ...