The Obama Oval Office is shown in 2010 with a new rug and coffee table. This office usually undergoes changes under each administration. (Brendan Smialowski/Bloomberg)

All eyes are on the White House this week. So we asked Matthew Costello, a senior historian for the nonprofit White House Historical Association, to give us a window into its inner workings during our our Home Front online chat.

Costello answered a lot of questions you might have on your mind as the occupants of 1600 Pennsylvania Ave. change from the Obamas to the Trumps. Here are a few edited excerpts from some of the topics he covered.

Furnished in Federal style furniture, the Green Room of the White House is the most informal of the state parlors and often serves as a space for interviews and social gatherings. (Bruce White/White House Historical Association)

How much can the new president change in the state floor? “The president of the United States arguably can change many things in the White House; however, all presidents have relied on experts and committees in order to maintain the historical integrity and tradition of the White House,” Costello said. The White House curator, the chief usher, the Committee for the Preservation of the White House, the Commission on Fine Arts, this is who the president and first lady will consult with regarding rooms, furniture and artwork.

This state dinner service was made for the Reagan White House in 1981 by Lenox China. The Reagan service featured a wide red border with a gilt rim and crosshatch pattern and a raised gold version of the president's arms. (Lenox China/White House Historical Association)

Why does each new president seem to order new official china? Because presidents entertain thousands of guests at the White House, they need many place settings. Plates become worn out, chipped or scratched with frequent use. During the 19th century the White House china cabinets were filled with a mixed collection of both personal china and state china from various administrations. “Not until Caroline Harrison starting organizing these sets and Edith Wilson devoted a room at the White House to displaying the china did these sets become much more significant for formal and state functions,” Costello said. Most modern presidents and first ladies like to design their own china pattern.

A full-length portrait of George Washington was painted by Gilbert Stuart in 1797, the final year of his presidency. First lady Dolley Madison famously saved the portrait from near-certain demise during the War of 1812. (White House Historical Association)

Is there anything from the administration of George Washington in the White House collection or is it all at Mount Vernon? Most people assume George Washington lived in the White House, but he did not, Costello said. He was integral to planning the national capital and selecting the site where the White House would be built, but he did not live to see his successor move in. Washington items that have survived in the White House collections include chairs, flatware and china. There are many more objects that feature Washington, such as artwork and sculpture. “Many of his things were scattered across the country; today Mount Vernon or the Smithsonian probably hold the largest collection of Washington objects,” Costello said.

What is the oldest thing in the White House? Some objects cannot be precisely dated, because the White House was burned by the British during the War of 1812. “Many of the White House holdings were destroyed in that fire and later tossed out in a gully south of the house,” Costello says. “Later renovations found pieces of the Madison chinaware. How cool is that?” Otherwise, there are pieces of Washington Cincinnati china that predate the White House itself. As far as an object that has remained in continual use: “One of my favorites is Gilbert Stuart’s famous painting of George Washington installed in the White House in 1800, removed during the burning, then came back in 1817. It has stayed in the White House since and today hangs in the East Room.”