Exterior, Metal Siding Material, and House Building Type Backyard excavation created a sunken courtyard, where the side entrance to a new 750-square-foot office space lies. The exterior is clad in Corian, a surface normally found on countertops. "The clients love that they can go to another wing of the house and have an office," says Brooks. "There's a physical seperation. We’ve designed it so in the future, if they close the firm, they can open up the door between the office and the dining room and connect the entire basement floor."  Photo 2 of 7 in Victorian Home in London Gets a Modern Office Addition