30TH

CONSERVATION OF
DECORATED SURFACES
BY FRANCESCA PIQUÉ AND LESLIE RAINER
THE CONSERVATION CHALLENGES PRESENTED BY DECORATED
surfaces are complex for numerous reasons, including the heterogeneous
materials used, the variation in size, the different types of
decoration, and the intimate link of the decorations to the structures
they adorn. The variety of decorated surfaces is as broad
as the range of cultures that create them. From prehistoric rock
art to ancient Roman mosaics to contemporary street art, we as
humans have always had the impulse to embellish, beautify, and
give meaning to our built environment.
Decorated surfaces can be two-dimensional, as in mosaics and
wall paintings—or three-dimensional, as in sculpted or carved relief
and ornamental stucco decoration. They are generally characterized
by their size and heterogeneous composition, made with materials
that include earth, lime, cement, and gypsum plasters; various
paints, glazes, and coatings; and stone and glass tesserae; all applied
to a variety of primary supports. The layering of these different materials
creates a surface that is often of high quality and refinement,
imbued with decorations that contain artistic and technical values,
cultural significance, and meaning that may be symbolic, religious,
or political. The surface is at the interface between the building and
the environment and is particularly vulnerable because it is both
exposed to external forces and intimately linked to a building system.
Collectively, these characteristics constitute the fundamental
conservation challenges for decorated architectural surfaces.
projects on decorated surfaces
In different parts of the world—and at various scales with different
objectives—the GCI has conducted projects addressing the
conservation issues of wall paintings, archaeological and historic
mosaics, and bas-reliefs.
The first GCI field project, initiated in 1986, was the conservation
of the thirty-two-hundred-year-old tomb of Queen Nefertari
in the Valley of the Queens, conducted with the Egyptian Antiquities
Organization (now the Ministry of State for Antiquities); that
effort focused on the tomb’s wall paintings. In 1987, the GCI began
working with the City of Los Angeles on a challenging project to
conserve, protect, and interpret América Tropical, a highly political
twentieth-century mural on cement-based plaster by the Mexican
muralist David Alfaro Siqueiros. It would be difficult to find two
examples of wall paintings so different—from the cultures that made
them to the materials and techniques of execution, as well as the
conservation issues presented. However, the conservation methodology
in both projects was similar, with a strong component of
study before intervention. In each case, post-treatment monitoring
and maintenance plans were developed and implemented.
The GCI has followed a methodological approach in its projects,
in close collaboration with its partners. Projects are developed
and interventions planned systematically, in the context of a sound
management structure, with interdisciplinary teams comprising professionals
from different and complementary specialties. This methodology
has ensured a strong scientific approach essential to under-
26 FALL 2015 | 30TH ANNIVERSARY
América Tropical, a 1932 mural by David Alfaro Siqueiros in downtown Los Angeles, where the GCI and
the City of Los Angeles were engaged in a long-term project to conserve, interpret, and provide public
access to the mural. Photo: Stacey Rain Strickler, J. Paul Getty Museum.