Construction under way for the new third floor, seen from the east wing in the summer of 1927. Historical Society of Washington The White House had always had an attic. Mrs. Woodrow Wilson added guestrooms and a painting studio for herself in 1913 in this space. A full third floor was not created until the Coolidge Administration, when problems with the roof structure were discovered. Recommendations were made to replace the old roof and 1817 timber structure. In 1927 William Adams Delano of the New York firm of Delano and Aldrich was called upon for advice. After studying Hoban’s 1793 drawing, he increased the pitch of the roof and lowered the floor to accommodate new guest and service rooms beneath a steel and concrete roof structure. At Mrs. Coolidge’s request, a sunroom facing south toward the river, the predecessor of the current solarium was added.