Category:Cathedral of Learning prior to 2007 cleaning

This is a category about a place or building that is listed on the National Register of Historic Places in the United States of America. Its reference number is 75001608.

This sub-category of images of the Cathedral of Learning at the University of Pittsburgh is reserved for images taken prior to and through the 2007 cleaning and restoration of Cathedral of Learning's facade.

The $4.8 million cleaning and restoration of the limestone facade took place from March through August, 2007.

As the Cathedral of Learning began construction in 1926, it almost immediately began to collect soot and grime on its exterior due to the heavy pollutants from Pittsburgh's then plethora of steel mills. This grime contained residue of carbons, sulfur dioxides, and gypsum that traps moisture and, over time, would cause further deterioration of the stone facade.

The West side of the Cathedral, which faces the wind, tended to self-clean and thus appears much less soiled in pictures, particularly at the upper floors. Images showing the East side of the building show a heavy, black/brown coating of dirt and grime. This was completely removed from the building except for one small portion of a wall in an interior light well which serve as a reminder to the city's industrial past. Cracked stones and lose mortar were also repaired.

Cleaning was accomplished by first pre-soaking with pressurized water to loosen materials and then blasting with a substance composed of recycled micron powdered glass rinsed off with pressurized water.[1][2][3][4][5][6][7]

Media in category "Cathedral of Learning prior to 2007 cleaning"

The following 52 files are in this category, out of 52 total.