LONDON (AP) — Maintaining big, older houses is never easy — as Queen Elizabeth II has learned of late.Buckingham Palace officials said Monday the ornate state dining room at the queen's official residence has been closed out of concerns for the safety of the ceiling.The palace says official functions set for the main dining room will be moved to other rooms in the vast palace in central London.An official statement says the problems were found during a routine survey."An issue was found with one of the ceiling beams in the roof space," the statement says.Officials are planning a complete overhaul of the palace to include rewiring, plumbing improvements, and removal of asbestos.