Mister Monday, Garth Nix
Start of The Keys to the Kingdom series. The House is the centre of all things. It's Architect left ten thousand years ago and her will was never executed. When Arthur is chosen as the heir he is dragged into a series of dangerous situations. Each of the current trusties is controls, and is named, for a day of the week. Monday controls the Lower House and is very lazy. There isn't anything very deep here but the books are exremely readable.
