A "new room in the house" is a tangible, easily definable addition to the scholarly base. For me, most recently, it involves acquiring a specialist's level of expertise of María Zambrano, a very interesting Spanish essayist, philosopher, influenced by Unamuno, with a fascinating trajectory as an intellectual. Once I get through reading all of the books in my university library by her and about her, I will have that room completed. It pays off to be a "completist" in some cases, because it is a lot easier to read everything than to try to figure out how much I need to read at a minimum just in order to write a little bit about her.
Lateral connections might follow. I would have to know about Zubiri, a philosopher who influenced her; to re-read the poetry of Emilio Prados, a poet she was close to. Those are other rooms I haven't built yet.