gallier hall phase ii: lafayette street elevation

GALLIER HALL
PHASE II: LAFAYETTE STREET ELEVATION
545 St. Charles Avenue | New Orleans, LA | 70130
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Submitted to:
City of New Orleans
Capital Projects Administration
Facilities, Infrastructure, and Community Development
City Hall | 1300 Perdido Street | Suite 6E15 | New Orleans, LA | 70112
Prepared By:
Cypress Building Conservation
614 Gravier Street | New Orleans, LA | 70130
May 8, 2015
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Architectural Material Analysis and Conditions Assessment of
Gallier Hall, 1917. John Teunisson Source: knowla.org
TABLE OF CONTENTS
INTRODUCTION....................................................................................................................................................................................................................................5
METHODOLOGY...........................................................................................................................................................................................................................6-9
BUILDING HISTORY/SIGNIFICANCE................................................................................................................................................................10-11
CONSTRUCTION.......................................................................................................................................................................................................................12-15
PREVIOUS RESTORATION CAMPAIGNS..........................................................................................................................................................17
FINDINGS/ANALYSIS........................................................................................................................................................................................................18-25
CONCLUSIONS........................................................................................................................................................................................................................26-27
FUTURE WORK......................................................................................................................................................................................................................28-29
CONDITIONS GLOSSARY.........................................................................................................................................................................................30-37
APPENDIX A: CONDITIONS ASSESSMENT, SPECIFICATIONS
AND SPECIFICATION DRAWINGS
Plan and Material Identification for the Lafayette Street elevation, James Gallier,
1845, Image stitched together from drawings provided by the City of New Orleans.
GALLIER HALL | 4 |
INTRODUCTION
In September 2014, Cypress Building Conservation was contracted by the City of New
Orleans to conduct a conditions assessment and material analysis of Gallier Hall’s façade,
following the fall of a large section of the building’s cornice. The façade assessment served
as the first phase of emergency stabilization of Gallier Hall. Its findings are presented in
a separate report. Phase II, initiated in March of 2015, focuses on the stucco and marble
elements of the Lafayette Street elevation.
A conditions assessment involves the thorough examination of the building materials,
deterioration patterns and identification of sources of deterioration. Understanding this
information is imperative in order to develop an informed and effective conservation
plan for the building. The conditions assessment process serves as the first step in the
restoration of Gallier Hall.
Gallier Hall is owned by the City of New Orleans and is located at 545 St. Charles Avenue
within the Central Business District. Built by renowned architect James Gallier Sr. in 1850, it
is considered to be the finest extant example of Greek Revival architecture in the City.
The design of Gallier Hall is modeled after the Erecththeum (built 406 B.C.) on the Athenian
Acropolis. Decorative elements of Gallier Hall, such as the cornice, architrave and fluted ionic
columns and capitals, are direct and accurate copies from this ancient Greek temple.
INTRODUCTION | 5 |
METHODOLOGY
A thorough conditions assessment involves a multi-step process that includes research,
documentation, survey, analysis and presentation.
I. ARCHIVAL RESEARCH
Archival research forms the foundation of all historic and material analyses of historic
architecture. Reviewing all existing documentation can reveal original construction methods,
subsequent restoration campaigns, previous deterioration issues, and building significance.
The City provided original architectural specifications written by architect James Gallier. Several
of Gallier’s drawings were also located, including sections and details. Also provided were
drawings from various restoration campaigns. Reference books on New Orleans’ architectural
history were an invaluable source of contextual and historical information.
Local archives were consulted including the Historic New Orleans Collection’s digital
catalog which was especially useful for locating historic photographs. Additionally,
research conducted on buildings similar to Gallier Hall in terms of physical materials and
deterioration patterns were consulted, specifically the Metropolitan Club and the Tweed
Courthouse in New York City and Market Hall in Charleston, SC.
1845 architectural drawing by James Gallier, Sr..
Source: City of New Orleans
GALLIER HALL | 6 |
II. MATERIAL ANALYSIS/IDENTIFICATION
In order to analyze deterioration patterns and their effect on the structure, the building
materials must first be identified in terms of their physical properties.
The marble type was identified through archival research and visual observation. In the
laboratory, samples of stone were observed under a stereomicroscope using reflected light
microscopy. Previous research conducted on this specific type of marble was consulted to
gain a better understanding of the material physical makeup and its means of deterioration,
including Frank Matero and Alberto de Tagle’s “Cleaning, Iron Stain Removal, and Surface
Repair of Architectural Marble and Crystalline Limestone: The Metropolitan Club” JAIC,
Volume 34, Number 1, Article 4 (1995) p 49-68.
Original stucco composition was determined by reviewing Gallier’s specifications. 20th
century restoration drawings indicated this original stucco was covered and/or replaced by a
high portland cement content stucco. Material analysis, including acid digestion, as well as
visual observation confirmed the presence of non-original cement stuccos.
III. CONDITIONS SURVEY
After the materials were
identified and located, the
various conditions were
defined in the field based
on a visual inspection of
the masonry units. These
conditions were compiled
in a conditions glossary for
reference, included in this
report.
METHODOLOGY | 7 |
IV. DOCUMENTATION
Documentation includes a written and visual recording of the building in its current state.
It is an essential component of an effective conservation plan as it serves a multitude of
purposes, including:
_establishing a baseline from which all future deterioration can be measured
_recording the building for historical and record keeping purposes
_helping to design and implement repair specifications
_effectively communicating the problem areas to the various interested parties
_monitoring restoration work
The conservators utilized rectified photography to document the building in its current state.
Rectified photography involves the use of a digital camera and design software to produce
a photographic representation of the subject without perspective or distortion. High
resolution photographs were taken in the field and then stitched together and manipulated
using Photoshop software. This process allows the creation of a high resolution image of
the entire elevation, allowing one to visualize all building components and their relationship
to each other. It also serves as an excellent document on which to record conditions and
their locations.
0’
LOCATION KEY
100’
50’
Rectified
photoelevation of the
Lafayette
Street elevation
GALLIER HALL | 8 |
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V. CONDITIONS MAPPING
Conditions mapping provides a way to visualize and understand the patterns of deterioration
and how they are related to each other and contribute to decay. Locations of conditions
were noted in the field on printed out versions of rectified photographs and drawings. They
were then transferred digitally and assigned specific hatching patterns to distinguish each
type using AutoCAD.
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EFFLORESCENCE
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Surface planar discontinuities that have become partially
separated from the parent stone
Areas of stucco that have become detached from the substrate. Includes
stucco areas directly adhered to brick and stuccos keyed to expanded metal
lath affixed to the substrate with ferrous fasteners
Crystalline deposits (ranging from loose and powdery to hard and compact)
resulting from the evaporation of water from a salt solution, which can form
on the surface of a porous materials exposed to air.
Mapped conditions on rectified photoelevation
DIFFERENTIAL EROSION
Surface weathering exhibiting large areas of coarse texture, pitting, or
reduction in surface details
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INCIPIENT SPALLING
DETACHMENT
100’
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Cracks of varying orientation and depth. Usually associated with
displacement/deformation or incipient spalling
50’
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CRACKING
0’
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CONDITIONS KEY
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SOILING
Blackening or discoloration of the marble surface due to biogrowth or the
deposition of airborne pollution. In areas exposed to the elements, biogrowth
is an indication of the path of moisture over the building surface.
REPAIR
A mortar based treatment system used as a surface repair for spalls, cracks
and losses
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Field notes
mapping
conditions
METHODOLOGY | 9 |
PREVIOUS COATINGS
Elastomeric paints and cementitious renders applied to marble decorative
elements
BUILDING HISTORY/SIGNIFICANCE
Architect James Gallier, Sr. submitted the original design specifications for what was then
referred to as Municipal Hall in 1845. The building was intended to serve as the Second
Municipality City Hall following the splitting of the City of New Orleans into three different
municipalities in 1836. The split was a result of growing tensions between Creole and
American powers. The second municipality was Anglo-dominated, and included the
neighborhood uptown of Canal to Felicity Streets, formerly known as Faubourg St. Marie and
often referred to as the American Sector.
When the three municipalities
of New Orleans merged again in
1852, the building assumed the
title of City Hall from the Cabildo,
an indication of the strengthening
American control over a once
Creole-dominated city. It remained
in use as New Orleans’ City Hall
until 1958 when the current modern
City Hall was completed and the
building was renamed Gallier Hall.
The City maintains ownership of the
building, using it for meetings and
events and also leasing it out as a
venue.
James Gallier, Sr was an Irish
immigrant (original name: Gallagher)
who arrived in New Orleans by
way of New York City in the midCity Hall as it appeared in 1864. Source: Marshall Dunham
1830s, a time of rapid growth
Photograph Album (Mss. 3241), Louisiana and Lower Mississippi
Valley Collections, LSU LIbraries, Baton Rouge, Louisiana.
and prosperity for the city. Gallier
quickly established himself as one
of the city’s premier architects, popularizing the neoclassical style that had been previously
introduced to New Orleans by Benjamin Henry Latrobe. His design for Gallier Hall is
considered the finest example of Greek Revival architecture that remains in New Orleans,
notable for its proportion and symmetry.
GALLIER HALL | 10 |
Robert Seaton was commissioned as the builder,
although Gallier took over this role during
construction. Construction was completed by
1850.
In 1974, the building was designated as a
National Historic Landmark.
Though Gallier Hall is no longer the center
of political life, it maintains an important role
in New Orleans’ social and cultural traditions.
Since the first Rex parade in 1872, important
officials and visitors have witnessed Mardi Gras
from its granite steps. Each year, the Kings of
Architect James Gallier, Sr.
Rex and Zulu stop their parade in front of Gallier
Source: knowla.org
Hall to toast the Queen of Carnival and the
Mayor. Visiting dignitaries are still welcomed at the building. It has been the site of mayoral
inaugurations, Super Bowl victory parties, countless other celebrations and important
events. Gallier Hall remains one of New Orleans’ most important civic buildings.
“Little Miss Lucille Newlin and
Mayor Behrman Welcome Rex
at City Hall, 1917.
Source: The Historic New
Orleans Collection
BUILDING HISTORY | 11 |
CONSTRUCTION
Gallier Hall is a three-story masonry structure of the Ionic order in the Greek Revival style.
The Lafayette Street elevation is comprised of a brick masonry backing rendered in stucco.
Blue Quincy granite comprises the first level of the structure. Tuckahoe marble was used for
a number of decorative elements on this elevation including the crown molding and upper
fillet, architrave molding, pilaster capitals and bases, chimney flues and parapet elements.
Gallier’s drawings indicate the window sills and paneling are marble as well, but this was not
able to be confirmed without further invasive investigation behind the cement stucco.
Gallier’s section drawing shows the building system and indicates the different materials and how they relate
to each other. Brown = marble elements. Red = brick masonry elements. Blue = granite. Gray= flagstone. Yellow
= wood.
GALLIER HALL | 12 |
0’
MATERIAL IDENTIFICATION KEY
50’
100’
LOCATION KEY
TUCKAHOE MARBLE ELEMENT
N
CYPRESS
DATE:
BUILDING
CONSERVATION
614 GRAVIER, NEW ORLEANS, LA 70130
(225) 936-2680 - [email protected]
cypressbuildingconservation.com
GALLIER HALL
545 ST. CHARLES AVENUE, NEW ORLEANS, LA 70130
Lafayette Street Elevation
Material Identification
4/1/2015
D.2
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Gallier’s original drawings detail building element materials
CONSTRUCTION | 13 |
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The brickwork was originally covered in a lime stucco with a limewash finish. It was scored
to give the appearance of expensive stonework, as costs prohibited this secondary elevation
from being constructed in stone. It is currently covered in a thick Portland cement render,
along with multiple coats of elastomeric paints. Several areas have been previously
repaired, indicated by a fiberglass and Portland cement render over metal lath, tied into the
masonry by ferrous metal pins. It is unknown whether any original stucco exists beneath
these modern coatings.
The cornice construction is different from that of the
façade, indicated by Gallier’s specifications as such:
“The hanging drip of the corner of the cornices shall
be supported by an iron rod one half inch square which
shall be suspended from the flagstone core by means
of iron hooks.”
The impermeable flagstone core was intended as
a waterproofing course, and is still visible from the
interior attic space. It also acts as a support system for
the overlying cornice.
Gallier Hall, section detail. Material types
are indicated by different colors: Brown
= marble. Red = brick. Blue = granite.
Gray= flagstone. Yellow = wood.
The dentils are comprised of a stack of bricks tied
into the brick masonry wall and supported from the
bottom by two wrought iron dentil ledge anchors.
Originally covered in a lime stucco, they were later
covered in a metal lath and modern cement stucco
system.
GALLIER HALL | 14 |
TUCKAHOE MARBLE
Tuckahoe marble is a stone sourced
from Westchester County, New York. It
was a highly popular building material
throughout the 19th century, prized
for its bright white color, durability,
and workability. While its use was
concentrated in the northeast, it was
shipped to New Orleans in order to meet
Gallier’s specifications for the “best and
purest description of white northern
A 20x microscopic image of the marble from Gallier
marble.”
Hall shows traces of tremolite, which presents itself in
rectangular bands.
There is some discrepancy as to the correct geological classification of Tuckahoe marble.
True marbles are metamorphic rocks formed by the recrystallization of calcite or dolomite.
Tuckahoe marble, because of its high magnesium carbonate content, is often referred to as
a dolomitic limestone or dolomitic marble. It is capable of taking a polish—a characteristic
of marbles—but it exhibits weathering patterns similar to that of limestone because it
maintains remnants of limestone-like bedding planes,
Tuckahoe marble is distinctive for
its medium to coarse grain size. It
maintains a high percentage of
dolomite and calcite, and contains
silicate minerals tremolite and
phlogopite, which can appear on a
weathered surface as dark mineral
inclusions. The stone also exhibits
traces of metatite and pyrite, ironbearing minerals that oxidize when
exposed to air and moisture, causing
visible intrinsic metallic staining.
Visual analysis of the cornice stone that fell from the building
shows the presence of bedding planes and discontinuities in
the stone where the stone detached.
CONSTRUCTION | 15 |
Cimini and Meric Restoration Drawings, 1967
GALLIER HALL | 16 |
PREVIOUS RESTORATION CAMPAIGNS
Archival research yielded insights into the building’s
early repair/maintenance history. An 1865
article mentions City Hall has gone through the
“whitewashing process,” indicating that limewash was
the original stucco finish. An 1893 newspaper article
detailing City Hall news discusses planned repairs
to the building, including “repairing and painting of
all stucco work. The stonework will be thoroughly
cleaned with acid. The entire building will be given
two coats of paint.”
The Daily Picayune, Dec. 21, 1865.
There are three known 20th-century façade restorations occurring in 1949, 1967 and 1984.
The 1949 restoration was triggered when the arm of Liberty, one of the carved marble
statues in the pediment, fell off the building and onto the sidewalk below. There are no
extant drawings from this restoration campaign. However, HABS documentation indicates
that the building was restored and cleaned at this time.
In 1967, Cimini and Meric Associates was engaged to restore and stabilize the marble
façade. Specification drawings indicate a series of marble repairs and the application of a
“waterproof coating” to the pediment..
Drawings from the 1984 campaign
indicate alterations to the drainage
details and include sandblasting
of stone caps to remove previous
asphalt coatings.
Scaffolding at pediment level, 1979-1983.
Source: Charles L. Franck / Franck-Bertacci Photographers
Collection, The Historic New Orleans Collection.
Though not well documented,
it is assumed that a number of
other repair campaigns, and at the
very least cleaning and painting
campaigns, have been implemented
since the building’s construction in
1850.
PREVIOUS RESTORATION CAMPAIGNS | 17 |
FINDINGS AND ANALYSIS
The Lafayette Street elevation’s masonry stucco and marble elements are actively
deteriorating, This is a direct result of previous incompatible treatments as well as the
introduction of modern systems within the historic building.
Previous restoration campaigns, while providing
a short term aesthetic fix, have had deleterious
effects on the building. The most harmful
intervention has been the application of modern
cement stuccos and elastomeric paint coatings
replacing and/or covering the historic original lime
stuccos and washes.
The Daily Picayune, Aug. 14, 1893.
Portland cement is a hard, impermeable material.
While this is beneficial in terms of durability,
it can serve to hasten the deterioration of the softer, porous masonry substrate by not
allowing moisture to travel out of the wall. In the same vein, elastomeric paints boast low
permeability, contributing to the entrapment of moisture within walls.
The installation of the HVAC system has introduced moisture into the building. The
system puts the building under positive pressure relative to the external environment,
pushing air and moisture from interior to exterior surfaces. Because of the impermeable
concrete surface covering, moisture is not able to travel to the exterior surface where it
would be allowed to evaporate. It is instead trapped inside the masonry wall, hastening
deterioration of metal and masonry systems.
It is known that as early as the late 1800s, the building was cleaned with acid. The
building’s Tuckahoe marble elements are highly soluble in acid, suggesting that marble
deterioration was initiated early in the building’s history. The 1984 restoration campaign
called for sandblasting as a cleaning method, which uses an excessive amount of pressure
and has harmful effects on masonry. Based on visual observation of deterioration, it is
reasonable to conclude that multiple other undocumented cleaning campaigns have
occurred using unsuitable products and abrasive methods.
The effects of these interventions are evident throughout the elevation’s surface, on both
stucco and marble elements.
GALLIER HALL | 18 |
STUCCO ELEMENTS
The dentils exhibit advanced deterioration. Cracks run the entire length of the dentil course,
indicating that every dentil is affected. The original construction of the dentils coupled
with incompatible repairs are responsible for this deterioration. Because of the applied
impermeable stucco layer and elastomeric paints, water is sitting within the dentils and
corroding the original wrought iron ledge anchors. As the metal corrodes, it expands,
causing cracking in the stucco. The eventual loss of brick or chunks of stucco is possible,
presenting life safety issues.
Corroding wrought iron hangers displacing metal lath and cement stucco
FINDINGS AND ANALYSIS | 19 |
Cracks are evident throughout the wall surface, indicating the path of moisture through
the building. A majority of these cracks have been previously repaired (painted over), as
indicated by discoloration. Some cracks have re-surfaced above these repairs, indicating
that they have only served to mask the problem and not treat it.
Cracks also demonstrate that the hard cement is an improper repair method. It is so rigid
that it is not allowed to move along with the natural settlement of the building. Advanced
cracking has led to detachment of the surface coatings.
Surface coating cracking and detachment within former repairs
GALLIER HALL | 20 |
Several areas of detachment are so advanced that they expose the masonry backing wall.
Most of these revealed previous repairs in the form of metal lath beneath a fiberglass mesh
and cement stucco render, tied into the masonry wall by ferrous metal pins. Because of the
constant levels of moisture in the wall, the pins are corroding and these repairs are failing.
These advanced areas of detachment allowed a better assessment of the exposed
underlying brick. The masonry was wet to the touch where there was no other possible
source of water (i.e. rain or leaks) affirming the source of moisture from HVAC systems. It
also confirms that the masonry substrate is in a continuously saturated state.
FINDINGS AND ANALYSIS | 21 |
Efflorescence, characterized by blistering of the paint surface, is evident throughout the
dentil course and frieze. It was also observed on interior plaster walls. Efflorescence is
another indication of moisture within the wall. When the historic bricks and mortars
are saturated, their natural salts are suspended in a soluble solution. Trying to reach an
equilibrium, the solution will push its way to the drier environment--either on the exterior
or interior of the building.. As the solution dries, the salts crystallize and remain on the wall
surface.
Efflorescence is
evident within
the dentil course
(above) and frieze
(left).
GALLIER HALL | 22 |
MARBLE ELEMENTS
Differential erosion is evident on select marble stones within the parapet. Erosion includes
evidence of pitting, visible as small depressions in the stone surface. Surface erosion is
expected as the building naturally ages and weathers. However, harsh abrasives, acids or
excessive pressure during cleaning have advanced these issues.
Surface pitting caused by abrasive cleaning
methods
Soiling is evident throughout the marble elements
The marble parapet elements also exhibit soiling and vegetative growth at joints. Soiling
and vegetation indicate the presence of a constant water source. While most of the
vegetation on the building consists of soft herbaceous perennials with relatively small, noninvasive root systems, there is some evidence of larger plants that may affect the building
structure.
Mortar deterioration and loss is evident within the marble parapet elements. Mortar serves
as the sacrificial element of a masonry structure and over time is expected to deteriorate.
However, it must be maintained in order to prevent water from entering and sitting within
the voids.
FINDINGS AND ANALYSIS | 23 |
The marble upper fillet is characterized by cement repairs and scaling. The coarse-grains of
the dolomitic marble factor into the way the stone deteriorates. Because Tuckahoe marble
is not fully metamorphosed, it maintains traces of bedding planes. These bedding planes
form discontinuities within the stone, acting as inherent weaknesses through which decay is
channeled. Similarly, mineral inclusions within the stone serve as inherent weaknesses that,
when exposed to the elements, will exacerbate erosion patterns. The cement repairs are
previous attempts to address these issues. However, incompatible cement repairs serve only
to further deterioration and leave an undesirable aesthetic effect.
GALLIER HALL | 24 |
Spalls, identified as detachment
of the marble elements, were also
noted, primarily in the molded
architrave and pilaster capitals. These
specific spalls are located within
vulnerable protuding elements and
are attributed to weathering and
differential settlement. The marble
pilaster capitals and bases have
been covered in cement, as well as
the marble window sills and panels.
While this does not pose serious
deterioration issues, it obstructs the
builder’s original intent by masking
the decorative marble elements.
FINDINGS AND ANALYSIS | 25 |
CONCLUSIONS
The conditions identified within the stucco and marble elements of the Lafayette Street
elevation show signs of continued deterioration. Previous repairs have served to either
obscure or advance decay mechanisms, not eliminate them. This assessment serves to
diagnose the causes of deterioration based on an advanced understanding of their patterns
and effect on specific elements This informed diagnosis will guide eventual treatment.
Past interventions must be learned from and not repeated.
Recommendations for repair and conservation treatments are detailed in the conservation
specifications submitted along with this report. The most important specification calls for
the removal of the cementitious stucco and replacement with a lime-based stucco and
limewash coating system.
When the cement stucco was applied to the building, it was considered an improvement
because of its durable qualities. However, the adverse effects it would have on the masonry
substrate were not considered. The cement stuccos are harder than the lime stuccos they
replaced. While this is considered good in terms of longevity, it is actually detrimental
to the relatively soft structure because its hard, durable qualities are also what make it
impermeable. If water is introduced to the masonry wall (and it inevitably will be, especially
in New Orleans), it will be trapped behind the impermeable layers and therefore not allowed
to dry out. Additionally, the hardness of the cement makes it more rigid. This makes it
prone to cracking as the cement will not be able to adjust to the natural movement of the
building.
The majority of deterioration conditions observed on the elevation can be attributed to this
cement stucco system. While HVAC systems have introduced moisture into the masonry
walls, it is the cement stucco that is not allowing the moisture out. Solutions therefore
must focus on how to move the water swiftly through the building where it can evaporate.
This solution is met with the application of a lime-based stucco and limewash coating
system, which provide a permeable, breathable protective coating over the masonry wall.
Additionally, these lime-based coatings are flexible and self healing, meaning they move
along with the building’s natural settlement.
GALLIER HALL | 26 |
Both the disadvantages of Portland cement and the advantages of lime-based stuccos
in the context of historic masonry are well studied, documented and established within
the science of building conservation. Specific reference material includes the National
Park Service’s Preservation Brief 2: “Repointing Mortar Joints in Historic Masonry Buildings”
and Preservation Brief 22: “The Preservation and Repair of Historic Stucco.” The City of
New Orleans’ HDLC provides a local source for reference in its Guidelines for Masonry and
Stucco.
Special attention should be directed to the dentils spanning the entire length of the
elevation. All of the dentils indicate advancing deterioration issues, and present the
eventual risk of masonry elements falling off the building.
This conditions assessment serves as the first step to implementing a strategic, informed
and well-developed restoration plan. By continuing to collaborate with a range of experts
including engineers, historic building experts, architectural conservators, and experienced
historic masonry contractors, the mistakes of well-intentioned but misguided past
interventions can be avoided.
It is absolutely vital that an informed maintenance strategy is implemented following the
restoration of the building. Just as with modern paint finishes, limewashes necessitate
periodic re-coating and maintenance. If regular maintenance is adhered to and necessary
repairs are conducted in a timely fashion using compatible materials, the long term
preservation of this building can be ensured.
CONCLUSIONS | 27 |
FUTURE WORK
WINDOW RESTORATION
The wooden windows were not included in this assessment, although they were observed
to be in need of re-glazing, repainting and repair. Future repair campaigns to this elevation
should include window restoration.
DOOR RESTORATION
Gallier’s original specifications are a remarkable resource for understanding the beautiful
details he intended for this building. In them, he specifies that “the entrance doors on both
streets shall be grained or bronzed and then twice varnished.” An early lithograph created
based on Gallier’s specifications demonstrates the effect these beautifully grained doors
have in contrast to the white building. The entrance doors should be restored to Gallier’s
original architectural intent.
1848 lithograph based on Gallier’s specifications, Thomas K. Wharton. Source: knowla.org
GALLIER HALL | 28 |
STREET LIGHT RESTORATION
Historic photographs
show the extant flapgpoles were
originally gas lanterns, and then
later modified to accomodate
one of the first electric lighting
systems in the City.
The restoration of both the door
and lampposts would contribute
to the beautification of the St.
Charles Avenue facade. The
upcoming tricentennial presents
a perfect opportunity to unveil
these improvements, allowing
Gallier Hall to stand once more
as a source of public pride.
FINDINGS AND ANALYSIS | 29 |
CONDITIONS GLOSSARY
The following conditions glossary illustrates and defines the deterioration conditions
identified on Gallier Hall through visual inspection.
MORTAR LOSS
DETERIORATED
JOINT MORTAR
GALLIER HALL | 30 |
Stone joints where the pointing mortar is completely loss
Stone joints where the pointing mortar is eroded, heavily
soiled, or repaired with a new mortar not matching the
original in appearance or properties.
DIMENSIONAL
LOSS
CRACKING
Localized stone loss greater than 2 square inches in area
Cracks of varying orientation and depth. Usually associated
with displacement/deformation or incipient spalling
CONDITIONS GLOSSARY | 31 |
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DISPLACEMENT/
and cracking or separation of stone resulting in
DEFORMATION
INCIPIENT
SPALLING
GALLIER HALL | 32 |
shifting of surface more than ½ inch out of plan
Surface planar discontinuities that have become partially
separated from the parent stone
DIFFERENTIAL
EROSION
MINERAL
INCLUSIONS
Surface weathering exhibiting large areas of coarse texture,
pitting, or reduction in surface details
Presence of inherent iron-bearing minerals such as pyrite and
hematite
CONDITIONS GLOSSARY | 33 |
REPAIR
STONE UNIT
REPLACEMENT
GALLIER HALL | 34 |
A mortar or resin based treatment system used as a surface
repair for spalls, cracks and losses
Previous repair using an entirely new and often different type
of stone
MECHANICAL
INTRUSIONS
ODUCED BY AN AUTODESK EDUCATIONAL PRODUCT
CORROSION/
METALLIC
STAINING
Localized discoloration resulting from the oxidation of
ferrous masonry anchors and pins.
Metal fasteners and protection elements that are drilled
into the masonry. Includes evidence of previous mechanical
intrusions that have been removed and repaired.
CONDITIONS GLOSSARY | 35 |
VEGETATION
GALLIER HALL | 36 |
PRODUCED BY AN AUTODESK EDUCATIONAL PROD
SOILING
The presence of large leafy plants and ferns on the building.
Associated to open mortar joints and areas of containing
sufficient moisture to sustain plant life
Blackening or discoloration of the marble surface due to
biogrowth or the deposition of airborne pollution. In areas
exposed to the elements, biogrowth is an indication of the
path of moisture over the building surface.
Crystalline deposits ranging from loose and powdery to hard
and compact) resulting from the evaporation of water from a
salt solution, which form on the surface of a porous material
exposed to air.
BY AN AUTODESK EDUCATIONAL PRODUCT
EFFLORESCENCE
CONDITIONS GLOSSARY | 37 |