The Ham-Ham Clubhouse is where the Ham-Hams hang out every day prior to Lapis and Lazuli. Afterwards they spend most of their time in Sweet Paradise until Here I Am, Clubhouse! where they return, but still visit Sweet Paradise.
Boss and Snoozer are generally the only inhabitants of it. Snoozer leaves the Clubhouse for the first time in The Snoozer Mystery! and then moves to Sweet Paradise near the end of I'm Parting, Clubhouse!. The Ham-Hams only discover him there in Lapis and Lazuli, though. He returns to the Clubhouse at the end of Here I Am, Clubhouse!.
The Clubhouse is locked up and concealed at the end of I'm Parting, Clubhouse! due to Boss leaving. He returns and the Clubhouse is opened again at the end of Here I Am, Clubhouse!.
The Clubhouse consists of several floors. The ground floor has a round table with chairs where the Ham-Hams usually discuss. There is a large comfy chair where Boss normally sits. There is also a TV which they never use either because it is broken or they just don't know how to work it. There is a ladder leading up to a cove where Snoozer usually sleeps on a mound of hay. It has a small slide leading to the ground floor. On the ground floor there are stairs leading upwards and eventually to the highest point, where there is a sort of zipline to ride in. It also holds Maxwell's study, bookshelves and the Ham-Ham Times 'printing press' that never got used after Maxwell's Big Scoop!. On the ground floor, there is also a large blue door that leads to Boss' bedroom. The main entrance/exit of the Clubhouse is also on the ground floor.