The Carnegie Free Library (419 Library St.) was listed on the National Register of Historic Places in 1973. Text was adapted from a copy of the original nomination document. 
The Carnegie Free Library of Braddock is an imposing Victorian brownstone structure. It was constructed in the Romanesque style in the tradition of H.H. Richardson. This structure was designed by William Halsey Wood and constructed in 1888-89 and 1893.
Stylistically, the library uses diverse units to achieve its Romanesque appearance. It is basically a two and three story edifice with one tower reaching four stories. The masonry work is coursed brownstone that has been cut into block form.
The front of the structure consists of a small gable roof structure, three stories high, flanked by two turrets with conical roofs that are two stories in height. A four story octagonal tower with a pyramidal octagonal roof sets to the right and back from the facade. A conglomeration of hip roof, three story sections is to the rear of the tower-turret section.
The main entrance has a brownstone semicircular arch with a keystone. A belt course runs around the facade splitting the first story level, being broken by windows. The tower and rear section has a similar but larger belt course, this running directly above the first floor window tops. The window lintels of most fenestration is a single flat brownstone slab. Similar slabs that protrude outward from the wall are used for sills.
Decorated stone work in an entangled floral leaf pattern and the inscription "Carnegie Library" is found on the facade above the second story level. A minor belt course is above the decorated stone work. The rear of the building carries an inscription that reads: "Carnegie Hall." Chimneys on this structure are done in brick and the roof in small tiles probably slate or shale. Other features of note are brownstone steps, arcaded semicircular windows in the tower section and later frame picture windows and ornamental stone work design on the first floor of both turret sections.
The front of this building was built by William Halsey Wood. The rear was most likely done by Alden and Harlow. Wood is known to have entered into competition for other local projects including the Pittsburgh and Allegheny Carnegie Libraries. This building represents the early work of Wood.
The building illustrates the prevailing Richardsonian pattern of large, asymmetrical, multi-level, rock face brownstone architecture. This manner of building with rough face brownstone used in heavy proportion flourished in the latter nineteenth and early twentieth centuries.
The main historical significance of this structure is that it was the first library that was endowed through the philanthropic efforts of Andrew Carnegie. Since this library several foundations have been set up in Carnegie's name and over 2,800 libraries have been given aid or established.