Stripping exterior paint on masonry

We have stripped exterior paint from a building constructed circa
1908. It has white Portland cement plaster with a crushed calcareous
aggregate and cast elements also made with white cement and crushed
aggregate.

The finished product has a green cast to it.  This is in contrast to
original surface color of off-white.  The off-white colored material
was found on locations that were never painted, and it is clear that
the green cast was not intended by the original architect.

We believe that Peel Away 7 was the product used.

Has anyone had this problem, that is, staining of cement based
masonry by the stripping process?

James Cocks
Conservation Technician
ARG Conservation Services
Pier 9, The Embarcadero
San Francisco, CA 94111
USA
415-421-1680 ext: 246
Fax: 415-421-0127


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                  Conservation DistList Instance 20:4
                 Distributed: Wednesday, July 19, 2006
                        Message Id: cdl-20-4-017
                                  ***