By 1912, the provincial economy had regained its strength, and architect Francis M. Rattenbury was commissioned to design an addition consisting of two wings of offices and a library to the south of the main block of the Parliament Buildings.
Using the same stone and a consistent architectural style, the three additions fit quite well with the main block. The library wing, standing largely free of the south side, gave Rattenbury an opportunity to include more ornamentation than was previously included in the rest of the structure. The exterior features 14 statues of historical figures that influenced British Columbia's past and six medallions of great literary figures. The rotunda of the library, with the exception of the scagliola columns, is lined with marble.
The Parliament Buildings originally held an apartment for a caretaker, including a sitting room, a living room, two bedrooms, and a pantry. There was no kitchen as the caretaker was entitled to eat in the Parliament Buildings' kitchen. These were converted to offices in 1914.