We currently have six of them (yes, insane. Four cages in or formerly quite lovely back room where we used to have nice dinners, etc) so we all need to study the video below. The past weekend we figured out that Dusty, our oldest chinchilla, joined "the family" around Christmas, 2008. So she's well over 12 years old.
They are truly remarkable creatures. Glad you have them in a separate room—they are nocturnal as you are aware and can be quite noisy!