Cob houses? I would love to build a cob house but i think i should start small.?

Is it possible or practical to combine cob with a more conventional house. I'm thinking about moving an exterior wall to make more space. Could i replace it with a cob wall? Could i add a cob room to an already standing house? The house is a dump and going to have to be torn down or renovated soon anyway. I want the final result to be a cobhouse whether I build it all at once or a piece at a time.