2024 Fall Online Exclusive: Historic Industrial Building Reuse and the Building Enclosure

THE INDUSTRIAL REVOLUTION in the United
States brought about large-scale industrial
facilities throughout the country. During the late
19th and early 20th century, these industrial
facilities were generally constructed using
mass masonry. Mass masonry structures are
composed of multiple-wythe brick masonry
and may include stone, concrete masonry units,
cast stone, and terra cotta. Mass masonry was
common for industrial structures during this
period, as brick masonry could be fabricated
from local materials and could be manufactured
in a size that was manageable for the labor
force. In addition, this type of construction was
adequate for the industrial use requirements of
the period, as the load-bearing masonry walls
had a long service life (Fig. 1).
Over time, these facilities were often
abandoned, whether it was from industry shifting
toward production overseas; requirements for
a new, modern industrial space; or closure of
businesses. With a shifted focus on sustainability
and the preservation of historic structures over
the last couple of decades, preservation and
reuse of historic industrial facilities has become
more prevalent. However, these facilities are
often inadequate for the requirements of
modern-day industrial use, which results in an
adaptive reuse approach. Adaptive reuse often
changes the occupancy type of the structure
and requires restoration of the facility along
with physical modifications to accommodate
the intended occupancy and to meet the current
design requirements for the new occupancy
type. Due to the location, history with
surrounding communities, desired industrial
aesthetic appearances, and sustainable use of
existing materials, adaptive reuse projects have
been presented as viable alternatives to new
construction. Reuse of existing building stock
in-situ is a sustainable building option for multiple
reasons: the structure and exterior enclosure
are existing and the embodied carbon/energy
within the existing on-site materials is retained;
there is a reduction in the materials which
must be provided and transported to the site
for construction; and the historic integrity of
the structure can be preserved. While the cost
of new materials is avoided and historic tax
credits are often granted, owners/developers
should be prepared for specialized costs, such as
including additional evaluation and design needs
stemming from working with existing conditions,
unexpected existing problems that will require
solutions during construction, the cost of skilled
restoration labor for the mass masonry, and the
cost of replacement materials which will maintain
the historical integrity of the structure.
Design considerations for restoration
and adaptive reuse involve knowledge
outside what is typically understood for
new, modern cavity wall construction. A lack
of understanding regarding the building
science related to the original construction
and the design considerations for the correct
performance of the building enclosure for its
new occupancy type can result in multiple
challenges during construction and future
occupancy of the structure. It is important for
the design/consulting team to communicate an
understanding of the cost, effort, and design
of the building enclosure system which is
required for adaptive reuse of historic mass
masonry structures. An understanding of and
investment in design and evaluation for adaptive
reuse projects can prevent costly errors during
construction and potential errors that will affect
the structure’s ability to meet the requirements
of its new occupancy.
Online exclusive
Historic Industrial
Building Reuse and the
Building Enclosure
By Paul Bielicki, AIA, NCARB, LEED AP;
William G. Lehne, PE, CIT II, sUAS-RP;
Michael Phifer, RBEC, CBECxP
This paper was presented at the 2023 IIBEC
International Convention and Trade Show.
Interface articles may cite trade, brand,
or product names to specify or describe
adequately materials, experimental
procedures, and/or equipment. In no
case does such identification imply
recommendation or endorsement by
the International Institute of Building
Enclosure Consultants (IIBEC).
©2024 International Institute of Building Enclosure C Fall 2024 onsultants (IIBEC) IIBEC Interface • 1
Figure 2. View of moisture-related damage to interior finishes. Figure 3. View of low permeability barrier installed at wall interior.
RESERVOIR SYSTEMS
When compared with modern-day cavity wall
construction, a mass masonry building enclosure
functions differently. While cavity wall systems
are intended to function as a barrier system with
a drainable cavity, a mass masonry building
enclosure is a reservoir system that is designed
to interact with moisture. A mass masonry wall
(reservoir) system impedes bulk water from
reaching the interior of the structure during a
wetting event by shedding a majority of the water
at the exterior surface. Water absorbed past the
exterior surface into the masonry is retained and
subsequently released once the wetting event has
passed. Depending on the exterior and interior
environmental conditions, water absorbed within
the masonry wall has the potential to dry to the
interior or exterior of the wall.
Originally, the potential for moisture drive to
the interior was accommodated, intentionally or
unintentionally, by leaving the interior masonry
exposed or by installing interior finishes with
high permeability. This was conducive to drying
that may occur through the interior masonry face.
Additionally, when compared with modern-day
structures, these structures did not have the
same requirements or considerations for energy
efficiency. Often, during the cold months, excess
heat was provided to the interior environment of
industrial facilities through radiant heaters, while
in hot months, fenestration with large, operable
panels provided ventilation.
The excess heat during the cold months
resulted in drying of the reservoir systems to
the exterior, while the lack of air conditioning
during the hot months mitigated colder interior
surfaces’ propensity for condensation. Modern
HVAC systems, which heat, cool, and often
dehumidify buildings, along with requirements
for higher R-values of the wall assembly, were
not factors for these structures during the period
when they were constructed; thus, they are
important factors to consider for adaptive reuse.
In the past few decades, an increasing number
of these mass masonry industrial structures
are being converted to modern living spaces.
Often, these renovations include the addition of
insulation to the wall assembly; less permeable
interior finishes, which are frequently moisture
sensitive (Fig. 2 and 3); and a conditioned
interior environment. Conditioning the interior
environment, installing insulation, and applying
moisture-sensitive interior materials create
conditions which can result in moisture-related
damage. This elevated moisture within the
interior finishes presents a potential for
biological growth.
Adding insulation to the exterior walls to
meet modern and code-required R-values
Figure 1. Overview of previous industrial mass masonry structure during construction of
adaptive reuse project.
2 • IIBEC Interface Fall 2024
requires special consideration for mass
masonry (reservoir) systems. Historic
preservation requirements, requirements of
the intended occupancy, and design analysis
of the hygrothermal response changes to the
building enclosure system and changes to
the building enclosure system requirements
are integral parts of a mass masonry
adaptive-reuse project.
BUILDING LAYERS AND DESIGN
ASSESSMENT
Assessing historic structures for adaptive reuse
requires a multifaceted approach. As a first
step, the designer/consultant should compile
and review the structure’s existing history
and documentation. Expectations for historic
integrity and allowable modifications should be
identified and agreed upon, as they will guide
design decisions. Once existing information
regarding the structure is known, an evaluation
of the code requirements for that occupancy
and the modifications of the existing structure
required to meet them can be performed.
It is important for the designer to properly
assess the modifications to the building
envelope system that are necessary for the
new occupancy requirements. Understanding
the performance of the in-place mass masonry
structure and any potential adjustments to
the system(s) is critical to ensure the system(s)
will function as intended. This is accomplished
through an understanding of building science,
use of hygrothermal analysis, and proper
detailing. The Glaser method, known as a
dew-point analysis, provides the location of
the condensation temperature. However, this
method is limited in the information it can
provide, as it does not take into account multiple
factors, such as built-in moisture and driving
rain, and is based on a steady-state condition.
Fraunhofer IBP developed Wärme Und Feuchte
Instationär (WUFI) software to perform dynamic
hygrothermal analysis. WUFI is a valuable tool for
understanding modifications to mass masonry
construction that are required for adaptive
reuse projects. WUFI provides the designer
with an evaluation tool to understand how the
modifications to the reservoir system will affect
its hygrothermal performance (Fig. 4).
SITE EVALUATION
Masonry restoration and evaluation will be
required as part of adaptive reuse. Over its
lifetime, a mass masonry reservoir system
will have a number of maintenance-related
items, including but not limited to repairs of
cracking within the masonry; repair of spalled
masonry units; repointing mortar joints that
have cracked, recessed, or separated from the
brick masonry units; removal of biological
growth; removal of abandoned fasteners or
abandoned steel elements; and repairing
abandoned penetrations (Fig. 5). Cracking must
be evaluated to determine if there are underlying
conditions that need to be resolved to prevent
the cracking from reappearing after the masonry
has been repaired and to identify potential
structural issues.
In addition to general maintenance items,
the porosity of the brick masonry may need to
be evaluated. Over time, brick masonry expands
from its kiln-fired volume and increases in
porosity. Increased porosity allows for additional
water to be absorbed into the masonry and for
the water to travel further within the reservoir
wall system.
Increased porosity of the brick and anomalies
within the brick masonry can prevent the
masonry from properly impeding the movement
of moisture to the interior during a wetting event
and can result in overloading of the reservoir
system or in bypasses through the reservoir
system. This can allow for bulk water intrusion
or for an increase in the moisture present at the
interior face of the masonry.
EVALUATION CONSIDERATIONS
On-site testing is recommended as part of
the mass masonry evaluation and adaptive
reuse design process. Because mass masonry
reservoir systems behave more as an integrated
unit compared with modern veneer cavity wall
systems, evaluation of mass masonry walls
for water intrusion can be more difficult than
evaluation of a cavity wall system. Testing is
often limited to a few components at a time
and may not capture the multiple components
contributing to overloading of the mass
masonry wall during a single test. The familiar
testing approach of starting at the base of the
area of concern, moving horizontally, and then
moving vertically is also applicable to testing
mass masonry. This should include care to
isolate testing areas and prevent overspray and
runoff from impacting locations outside of the
test. However, documentation of the condition
and locations of the areas tested prior to the
current test is a key factor in understanding
what conditions are contributing to the
overloading of the masonry system. There is a
potential that the previously tested areas will
contribute to the overloading of the system,
resulting in water intrusion observed during
a later test. When evaluating mass masonry
walls for water intrusion, two key factors
help to interpret the results and guide the
recommendations:
• system vs. condition and
• failure mode.
Water intrusion through a mass masonry
reservoir system may be the result of an
Figure 5. Representative view of masonry
Figure 4. WUFI analysis results in animation still. requiring restoration.
Fall 2024 IIBEC Interface • 3
inability of the building envelope system
to meet the requirements demanded of the
system as designed and/or it may be the result
of degradation or anomalies within the building
envelope system. It is important to distinguish
which aspect of the system is being evaluated
during testing: its adequacy or its condition.
A system that has performed well in the past
may have additional components installed
that result in moisture-related failures of the
assembly or may be introduced to additional
requirements that are outside of its original
design. These can include installation of new
interior finishes, installation of additional
thermal resistance, installation of new exterior
applications to the mass masonry, or changes
to the interior environmental conditions.
Evaluation of the interior environmental
conditions, destructive testing to evaluate
components which may have been added to
the mass masonry system, evaluation of site
and roof drainage, evaluation of observed
cracking to determine if there are underlying
conditions, and evaluation of potential rising
damp provide information on whether the
existing building envelope system needs to
be modified to adequately meet the current
performance requirements. Evaluation of the
condition of the masonry for maintenance items
such as cracking, debonding of the mortar from
the masonry, recessed mortar joints, biological
growth or foreign materials, condition of the
fenestration and the installation, porosity of
the masonry, and spalling provides insight into
the restoration efforts which will be required to
restore the system back toward its original level
of performance.
The failure mode observed while testing
provides valuable information to assist the
designer/consultant with recommendations and
repairs. The quantity of water intrusion observed
should be noted to inform the designer of the
severity of the issue they are attempting to
address. Water intrusion through mass masonry
may be observed as a damp portion of the
masonry wall that does not result in bulk water
intrusion, a damp portion of the wall that results
in bulk water intrusion through multiple gaps and
cracks within a masonry wall area, or bulk water
intrusion that is confined to a condensed entry
point. While a damp interior masonry surface may
not result in bulk water intrusion, it can contribute
to failure of interior coatings and finishes by
increased moisture drive to the interior and by
increasing the moisture content at the interior
finish-to-masonry interface. When water passes
through masonry, or cementitious materials
such as mortar, it can transport minerals from
within the masonry and deposit them on the face
of the masonry; this is known as efflorescence.
Coating failure from elevated moisture or vapor
drive typically consists of unadhered pockets
of the interior coating (Fig. 6). When opened,
efflorescence within the unadhered coating
pocket is often observed.
Water intrusion that starts as a damp portion
of the masonry and results in bulk water
intrusion through multiple anomalies within an
area of the masonry wall points to overloading of
the masonry reservoir system, which may require
greater effort to restore the mass masonry.
Water intrusion at a condensed interior entry
point indicates a more direct pathway through
the masonry wall (Fig. 7).
SITE EVALUATION
PROCEDURES
The following are evaluation procedures that
can be utilized when assessing mass masonry
reservoir systems.
ASTM E2128
ASTM E2128, Standard Guide for Evaluating
Water Leakage of Building Walls,1 provides an
outlined standard for evaluating water leakage
of building walls. This includes, but is not limited
to, references to AAMA 501.2, Quality Assurance
and Diagnostic Water Leakage Field Check of
Installed Storefronts, Curtain Walls and Sloped
Glazing Systems (Monarch Type B-25 brass nozzle
testing);2 ASTM E1105, Test Method for Field
Determination of Water Penetration of Exterior
Windows, Skylights, Doors, and Curtain Walls,
by Uniform or Cyclic Static Air Pressure Difference
(spray rack testing);3 and AAMA 511, Voluntary
Guideline for Forensic Water Penetration Testing
of Fenestration Products.4 The primary purpose of
ASTM E2128 is to “recreate leaks that are known
to occur,” not to “demonstrate code compliance
or compliance with project documents unless
such deviations are actually related to the
leakage problem.”1
Modified ASTM E1105
A modified ASTM E1105 procedure is available
for testing of masonry (Fig. 8). It is titled Using
Modified ASTM E1105 to Identify Leakage
Sources in Building Wall Systems.5 This
modified procedure recommends utilization
of a similar water application rate, but instead
of a 15-minute test duration, a 30-minute test
duration is specified. This modified method lists
Figure 6. Representative view of unadhered pockets of interior coating
with efflorescence behind unadhered coating.
Figure 7. Representative view of damp portion of wall with water
weeping from anomalies at the interior masonry surface.
4 • IIBEC Interface Fall 2024
construction of a negative pressure chamber on
the interior as optional.
Masonry Absorption Testing In-Situ
When evaluating masonry for absorption of
water at the exterior surface, two methods
currently exist: RILEM tube testing and
ASTM C1601, Standard Test Method for Field
Determination of Water Penetration of Masonry
Wall Surfaces.6 The data obtained from this
testing provides information regarding the
porosity of the brick masonry and whether
options to reduce porosity should be considered.
This test method is also useful in evaluating
coating materials as previously described to
determine the efficacy of the material being used
in conjunction with the masonry of the structure.
A baseline reading of the material must first
occur, followed by application of the coating
material and subsequent testing to compare the
results to determine if the material is functioning
as intended.
RILEM Tube Testing
Technical committees, through Reunion
Internationale des Laboratoires d’Essais et de
Recherches sur les Materiaux et des Constructions
(RILEM), developed a testing method for
evaluating water absorption rates of masonry
exposed to water at the exterior surface. This
testing method is commonly called the RILEM
tube test. This procedure involves using a
graduated cylinder with an open end attached to
the wall using putty to ensure a tight seal. Water
is filled to the appropriate level (the water level
loosely correlates to wind loading) and is allowed
to remain within the cylinder for a measured
period of time. At the end of the intended
test time, the water level is measured, and an
absorption rate is calculated from the change in
water level over time and from the surface area
of the wall that is exposed to the water in the
RILEM tube. When utilizing RILEM tube testing,
different sample locations should be tested,
including the face of brick, mortar T-joints,
mortar bed joints, and mortar head joints.
ASTM C1601
ASTM C16016 measures water penetration of
an in-situ masonry surface. This test involves
mounting a minimum 12 square foot, closed
chamber to the exterior side of the masonry
specimen. The chamber is positively pressurized,
and water is introduced within the chamber as
a sheet flow down the face of the masonry. The
water applied to the masonry is drawn from a
well with an initial water volume and is returned
to the well through an outlet at the bottom of
the chamber, creating a closed testing system
where water can only escape by absorption
into the masonry. The change in water volume
over time and the change in water level at the
end of the test correlate to the water absorbed
into the masonry through application to the
exterior surface.
Both RILEM tube testing and ASTM
C1601 have benefits and limitations. RILEM
tube testing is easier to set up and less
time-consuming compared with ASTM C1601
testing. A RILEM tube test can be completed
by one person in the span of 15 to 30 minutes,
with multiple RILEM tube tests running at
the same time. An ASTM C1601 test can take
between four and six hours to complete and
often requires two people to set up. However,
the exposed masonry surface area during
a RILEM tube test is 0.88 square inches,
compared with the minimum exposed masonry
surface area during an ASTM C1601 test of
12 square feet. According to an article by the
National Concrete Masonry Association, “A
study conducted at the University of Wyoming
concluded that 1,665 tests would need to be
conducted for every 12 ft2 (1.11 m2) of wall
surface being evaluated in order to achieve a
sample error of 10% or less [8]. Hence, drawing
any conclusions about the water penetration
characteristics of an entire wall assembly
based on 50, 100, or even 500 tests can be
speculative at best.”7 This does not mean that
data from RILEM tube testing is not useful,
but rather that there are additional limitations
on the conclusions that can be drawn from
the data. RILEM tube testing provides a
simple and portable evaluation tool to make
relative inferences regarding the absorption
performance of the masonry. However, if the
designer/consultant desires to measure and
report in-situ surface water absorption rates
for masonry, ASTM C1601 should be utilized.
Both tests are best used to test before and
after results for a mass masonry wall. While an
absorption rate is obtained from ASTM C1601,
the test does not include pass/fail criteria.
Air Leakage Testing
ASTM E779, Standard Method for Determining
Air Leakage Rate by Fan Pressurization8 is a
quantitative test for measuring building air
leakage. ASTM E1186, Standard Practices for Air
Leakage Site Detection in Building Envelopes
and Air Barrier Systems9 is a qualitative test for
identifying potential sources of air leakage.
Both test methods use a mechanically
produced pressure differential across the
building envelope (pressurization and/or
depressurization). ASTM E1186 has multiple
methods for utilizing tools to identify air leakage
locations, including infrared thermography,
hand-held or theatrical smoke, pressure
chambers, and bubble gun testing.
Detailing
As mentioned earlier in this paper, mass masonry
walls do not conventionally contain drainage
planes and do not have cavities containing
insulation or open cavities where insulation may
Figure 8. Representative view of Modified ASTM E1105 testing of mass masonry.
Fall 2024 IIBEC Interface • 5
be installed. When designing repairs or retrofit
conditions needing bulk water and water vapor
resistance, the wall must be treated as a barrier
system. As will be discussed, this simply written
requirement can create other issues for the
designer which also must be addressed.
Because mass masonry walls provide water
shedding and reservoir retention, the first
approach to reusing mass masonry walls is to
repair the existing masonry components back to
original conditions, or as close as is possible with
modern methods. This includes items discussed
previously. The specifics of masonry repair can
be found in many different publications and are
not covered in detail within this paper. However,
the proper design and specification of the
mortar joints will impact how well the wall can
shed water.
As noted earlier, the design of the new
mortar joint is critical. Not only the joint shape,
but also the pointing mortar’s composition
should be carefully selected. Depending upon
the historic nature of the wall and whether
the original wall design is legally protected by
historic regulations, a designer should specify
the mortar joint geometry to be concave. Many
historic masonry walls were constructed with
joints struck flush with the wall face or raked
back from the wall face. In some cases, the
authors have seen joints raked as much as ½
inch back from the wall face. Numerous studies
have been performed and results published
regarding how these types of mortar joints
have far inferior resistance to water absorption
compared with a concave struck joint. During
repair design, the use of a concave struck mortar
joint should be considered. The concave shape
helps the joint resist moisture intrusion. The
mortar composition should be soft or softer
and should have porosity similar to or greater
than the existing mortar. Throughout history,
mortar joints have been the “sacrificial” portion
of a mass masonry wall and were softer than
the surrounding brick. If any conditions were to
place stresses on the wall, including the natural
expansion of the brick masonry units over their
lifetime, the mortar joints would degrade to
prevent the alternative face spalling of the brick
masonry units. To replace historic mortar with a
more modern, harder mortar may cause internal
stresses to fracture the now softer masonry
units, rather than the mortar joints. To match
the existing mortar strength, petrographic and/
or chemical tests should be performed on wall
samples. At a minimum, mortar much softer
than modern mortars should be selected for
historic masonry mortar pointing. This is a
durability design decision, though, and should
be thoughtfully considered. If the reader wishes
to know more about selection of specific historic
mortar mixes and why concave joints resist
bulk water better than other joint geometries,
numerous articles and research results can
be found within the industry and academia
addressing the specifics of these topics.
The historic nature of mass masonry walls
predicates that most were constructed prior to
the mechanical conditioning of interior spaces.
The reuse of buildings built with mass masonry
walls creates a state where the mass of the
wall alone must separate interior and exterior
environmental conditions. These environmental
conditions may often be on opposite ends of the
environmental spectrum, such as hot/humid
outside and cold/dry inside. Also, given the mass
of a mass masonry wall, there is intrinsically
some insulative value, but not to a degree which
would help prevent condensation on the colder
side of the wall. In addition, masonry, being an
absorptive material, will naturally allow water
vapor to be transported from the high-pressure
side of the wall to the low-pressure side. This
makes the design of a water-resistant exterior
wall using existing mass masonry a difficult
endeavor. No matter the final design solution,
the wall design and expected wall performance
should be coordinated with the design of the
HVAC system. It is likely the HVAC system may
have to accommodate thermal and humidity
conditions affected more by the exterior
environment than would occur in a more modern
building. A discussion about HVAC design is
beyond the scope of this paper, though, and will
only be touched upon, as mass masonry walls are
impacted by the differences between the interior
and exterior environments.
Given that the nature of mass masonry
requires the mass of the wall to respond as a
barrier to air and vapor transmission, design
options are rather limited. Bulk water must be
controlled at the exterior masonry face. Vapor
transmission could be controlled at the interior
or exterior face but, given that the bulk water
should be controlled at the exterior face, the
design should not develop a condition where
any moisture could be trapped within the
mass of the wall between interior and exterior
control layers.
There are multiple ways to make a mass
masonry wall perform better as a barrier system
to liquid water. These are typically in the form
of coatings which are applied to the exterior
surface of the building. The desired efficacy
and aesthetic results will influence a designer’s
decision as to which method is selected. Any
method selected may affect the final appearance
of the building and could impact any historic
designation the building may carry.
More difficulty is imparted to a mass masonry
renovation project when designing approaches
to thermal barriers. Raising the thermal
resistance of a mass masonry wall requires
adding insulation to the wall. Adding it to the
interior side of the wall, which is the only place to
physically locate it without changing the exterior
aesthetics, changes the thermodynamics of
the wall. The interior masonry face, which was
once exposed to the conditioned or tempered
interior air, is now thermally separated from the
interior, making it colder. Depending upon the
geographic building location, this could make
the interior masonry face reach temperatures
where condensation of interior water vapor
could occur, should that vapor be allowed to pass
through the insulation. Interior vapor barriers
may be used but could also create a condition
where moisture within the masonry which
evaporates toward the building interior could
become trapped within the wall behind the
vapor barrier. This approach may influence the
selection of the liquid water barrier design for the
exterior masonry face. In this case, it would be
imperative to use a liquid water barrier with high
permeability, allowing any water vapor within the
masonry to dry to the exterior of the building and
not become trapped behind the interior vapor
barrier. Interior vapor barrier selection should
also be very carefully considered with some
consideration toward “smart” vapor barriers,
which can change permeability depending upon
the level of humidity present.
As can be expected at this point, the
hygrothermal changes stemming from modern
exterior wall renovations are complicated
and difficult to determine through general
knowledge of thermal movement from hot to
cold and vapor movement from high pressure
to low pressure. This is where WUFI analyses
performed on the original wall design and then
on various design options can greatly help the
designer better understand how a new wall
design may respond to the environmental
conditions and whether over time, it will have
an opportunity to dry and remain within
the parameters where condensation and
the possible biological growth associated
with moisture and many building materials
do not form.
Water-Repellent/
Waterproof Coatings
Often, water repellents and waterproof coatings
are used interchangeably; however, there are
important differentiating factors that should be
understood prior to approaching restoration.
The National Parks Service brief “Assessing
Cleaning and Water-Repellent Treatments
6 • IIBEC Interface Fall 2024
for Historic Masonry Buildings”10 describes
water-repellent coatings as breathable,
meaning they allow vapor to pass through
the system while keeping liquid water from
penetrating the surface. Conversely, waterproof
coatings are intended to seal the surface from
liquid water and vapor.
While the first line of defense against water
intrusion should be properly repointed and
repaired masonry, often water intrusion may
still appear, whereby alternative options such
as coatings as described may be considered. If
moisture intrusion continues following proper
repairs, consultation with an architectural
conservator should be made to determine
applicable systems and approach strategies.
These coating systems are often inaccurately
prescribed to remedy bulk water intrusion
without understanding the function of the wall
system. Most historic masonry structures have
survived hundreds of years without the use of
coating materials and, if properly maintained,
should continue to function as designed.
Detailing coatings around wall openings, such
as windows and doors, can be rather difficult. In
a wall containing a drainage plane, fenestrations
can be sealed to the barrier creating the drainage
plane. This creates continuity of the water barrier
from the drainage plane to the fenestration.
With coatings applied to the building exterior,
or those which are absorbed into the masonry
units, creating a continuous system requires
removal of the sealants around the fenestrations
and application of the coating to a point beyond
where a proper seal may be made between the
fenestration and the wall. Ideally, all fenestrations
would be removed prior to installing the coating.
This allows the coating to wrap the entire
fenestration opening. However, water-repellent
coatings are often the type which is designed
to penetrate the masonry and can be relatively
transparent. Ensuring the fenestration sealant is
continuously sealed to the coating around the
perimeter of all fenestrations cannot be ensured
without water testing the fenestrations following
the completion of the coating and installation
of the fenestration sealant. It should be noted
that these systems often have wind- driven rain
warranty limitations, are limited in their warranty
duration, and generally require maintenance after
10 years.
CASE STUDIES
Terracon has been involved with several projects
where historic industrial buildings, namely mill
buildings in the southeastern US, have been
repurposed for multifamily residential or office
buildings. The historic appearance of the building
was desired to be retained while providing a
conditioned interior for the occupants. With
most of these projects located in the southern
US, the design cooling load was high, and the
vapor drive was predominantly from the building
exterior to the interior. The locations of the air
and water management planes required scrutiny.
Selection of building enclosure improvement
materials and detailing of transitions between
components went through several iterations and
reviews to determine the best solution for the
given conditions.
Case Study 1
A former cotton mill constructed in 1897 was
reimagined as a high-end apartment complex
(Fig. 9). The two-story structure consisted
of brick mass masonry wall construction
with stucco applied over the brick at various
locations. The spaces include primarily
residential units, leasing office, recreational
space, fitness room, and clubhouse.
Construction consisted of interior and exterior
renovations, including window replacement.
The existing window systems were 12 feet
tall with segmental arched tops replaced as
part of the renovation. The arched head and
jamb interfaces were mass masonry with the
sill finished in concrete (Fig. 10). Shortly after
the building opened, leaks were reported
by residents at windows. Water testing was
performed on the assemblies isolating the
fenestration system and the surrounding
construction independently. Windows
installed in mass masonry construction require
particular attention to detail, as the interfaces
surrounding the windows provide opportunities
for moisture to penetrate the masonry and
migrate beyond the system and into the interior
space. Upon investigation, it was determined
that water intrusion was a combination of the
assembly construction including sealant joints
as well as migration through the masonry
adjacent to the fenestration. Recommendations
provided to the client first included the repair
of the fenestration assemblies. Because the
fenestration assemblies were customized,
limited modifications could be provided
Figure 9. View of cotton mill constructed in 1897.
Figure 10. Representative view of
new fenestration installed in existing
mass masonry wall opening.
Fall 2024 IIBEC Interface • 7
to mitigate the moisture surrounding the
opening; therefore, the perimeter of the
assembly was detailed using masonry sealer.
Case Study 2
A firehouse constructed circa 1890
comprising a load-bearing, multiple-wythe
brick masonry structure with a wood-framed
interior was remodeled in the 1930s,
including the installation of cement stucco
on the brick masonry wall exterior. At some
point in the building’s history, cement stucco
was also applied to the interior. A second
coat of softer, possibly gypsum-based stucco
was added to the interior over the cement
stucco. When the building was adapted to be
a conference center, modern HVAC systems
were added and due to its location in the
southeast US, and the numbers of people
who can fill the conference center, it is often
in cooling mode, which is also drying the
interior environment.
In recent years, the building owner had
repaired numerous problems with the
exterior and interior stucco (Fig. 11). The
exterior cracks had been repaired in 2010 and
2016, yet the interior continued to experience
water damage in the form of the soft stucco
coat spalling and the interior paint bubbling.
Terracon was contracted to do visual
observations and water testing to determine
the source of the water intrusion and interior
damage (Fig. 12).
The visual observations and testing revealed
numerous locations where liquid water was
infiltrating the stucco substrate (Fig. 13).
Through capillary flow and the drying of
the exterior wall to the building interior, a
significant amount of liquid water and water
vapor were damaging interior finishes (Fig. 14).
Difficulty arose in understanding which exterior
conditions created which interior damage. Water
from testing was revealing itself on the interior
in locations unexpected by the testing team.
For this reason and to ensure a continuous
barrier system could be installed around the
entire building, a waterproof coating with high
permeability was specified for the exterior. All
the windows were specified to be replaced,
which allowed the coating to wrap the window
openings and the perimeter sealant to bridge
between the window frame and the coating at
every window.
Because the application of the coating
would likely trap some of the existing moisture
within the wall and create a condition where
the path of least drying resistance was
toward the interior, the owner was advised
the interior repairs would need to wait for a
Figure 11. Representative view of cracking in stucco. Figure 12. Representative view of forensic water testing.
Figure 13. Representative view of original
fenestration.
Figure 14. Representative view of soft stucco
wrapped into the window rough opening.
8 • IIBEC Interface Fall 2024
couple of months. This was to ensure most of
the walls would be dry enough to not create
further problems with interior finishes. The
interior finishes were also addressed. The soft
stucco was recommended to be removed and
replaced with cement stucco, which would
be less susceptible to moisture damage.
To help allow the wall to dry to the interior,
high-permeability paint was specified.
In addition, the roof was nearing the end
of its serviceable life. This allowed the design
team to develop a parapet cap solution, making
the new coating continuous with the roofing
system. Therefore, the entire building enclosure
would be continuous and tight from the grade
to the roof.
CONCLUSION
In closing, historic industrial mass masonry
buildings are a popular candidate for adaptive
reuse, such as multifamily dwellings and
commercial buildings. These new uses within
historic enclosures present design and
performance challenges which can create
conditions detrimental to interior construction
and air quality and have negative impacts
upon the users. By understanding the building
science behind how mass masonry walls
perform and how the changes to the interior
environment influence performance, the
designer can better make repair decisions and
material selections, which can extend the life
of the building and provide a sustainable and
financial benefit for the building owner.
REFERENCES
1. ASTM Subcommittee E06.55, Standard Guide for Evaluating
Water Leakage of Building Walls, ASTME2128-20 (West
Conshohocken, PA: ASTM International, 2020).
2. AAMA (American Architectural Manufacturers Association),
Quality Assurance and Diagnostic Water Leakage Field Check
of Installed Storefronts, Curtain Walls and Sloped Glazing
Systems, AAMA 501.2 (Schaumburg, IL: AAMA, 2015).
3. ASTM Subcommittee E06.51, Standard Test Method for
Field Determination of Water Penetration of Installed
Exterior Windows, Skylights, Doors, and Curtain Walls, by
Uniform or Cyclic Static Air Pressure Difference, ASTM E1105
(West Conshohocken, PA: ASTM International, 2015).
4. AAMA (American Architectural Manufacturers
Association), Voluntary Guideline for Forensic Water
Penetration Testing of Fenestration Products, AAMA 511
(Schaumburg, IL: AAMA, 2008).
5. Norbet V. Krogstad, Dennis K. Johnston, and Richard
A. Weber, “Using Modified ASTM E 1105 to Identify
Leakage Sources in Building Wall Systems,” in Water
Leakage Through Building Facades, ed. R.J. Kudder and
J.L. Erdly, STP1314-EB (West Conshohocken, PA: ASTM
International, 1998).
6. ASTM Subcommittee C15.04, Standard Test Method for
Field Determination of Water Penetration of Masonry Wall
Surfaces, ASTM C1601-22a (West Conshohocken, PA:
ASTM International, 2022).
7. NCMA (National Concrete Masonry Association), “Are
RILEM Tubes an Effective Method of Evaluating the
Water Repellent Characteristics of CMU?,” NCMA TEK
FAQ 25-20, 2020, https://ncma.org/resource/faq-25–20.
8. ASTM Subcommittee E06.41, Standard Test Method for
Determining Air Leakage Rate by Fan Pressurization,
ASTM E779-19 (West Conshohocken, PA: ASTM
International, 2019).
9. ASTM Subcommittee E06.41, Standard Practices for Air
Leakage Site Detection in Building Envelopes and Air
Barrier Systems, ASTM E1186-17 (West Conshohocken,
PA: ASTM International, 2017).
10. Robert C. Mack and Anne Grimmer, “Assessing Cleaning
and Water-Repellent Treatments for Historic Masonry
Buildings,” in Preservation Briefs 1 (Washington D.C.: U.S.
Department of the Interior, National Park Service Cultural
Resources, 2000), 12–13.
ABOUT THE AUTHORS
Paul Bielicki is a
senior architect at
Terracon Consultants
with over 30 years of
experience. He has
managed or technically
developed a variety
of building projects
including offices,
performing arts centers,
and health care. Paul
holds an architecture
undergraduate degree, a Master of Architecture,
and a Master of Science in Structural Engineering.
He is the current co-chair of the Charlotte
Building Enclosure Council and is a mentor
with ACE Mentoring Charlotte. After 25 years in
the building design profession, his interests in
building enclosures and love of problem solving
led to building enclosure consulting. With
Terracon, Paul investigates building enclosure
failures, develops designs for repairs, and peer
reviews building enclosure designs. Paul is also
researching building component reuse, Design for
Deconstruction (DfD), and adaptive building reuse
through modifying existing building enclosures
to perform properly with contemporary interior
environment control.
William Lehne is a
graduate of Clemson
University with a
bachelor’s degree
in civil engineering,
emphasis in
structures. He has
been in the industry
since 2015. His
work experience
includes water
testing for forensic
evaluation and for performance verification;
whole building air testing; use of infrared
to identify residual moisture and sources of
air leakage; forensic structural evaluations;
structural design of light-framed wood
residential and multi-family structures; roof
design; building evaluations for insurance
claims; and evaluation of masonry for
restoration of historic structures. He is
trained on the utilization of WUFI Pro and is
a registered sUAS (drone) pilot.
Michael Phifer is
a graduate of the
University of North
Carolina Charlotte
with a bachelor’s
degree in Civil and
Environmental
Engineering. Since
2013, Michael
has worked in
the Facilities
Engineering Division
at Terracon Consultants Inc. Michael’s
experience includes building evaluation,
design, peer review and quality assurance for
building enclosure systems for both new and
existing building construction. In his current
role, he is responsible for operations of the
Charlotte, North Carolina Facilities Group.
PAUL BIELICKI, AIA,
NCARB, LEED AP
WILLIAM G. LEHNE,
PE, CIT II, SUAS-RP
MICHAEL PHIFER,
RBEC, CBECXP
Please address reader comments to
chamaker@iibec.org, including
“Letter to Editor” in the subject line, or
IIBEC, IIBEC Interface,
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Raleigh, NC 27601.
Fall 2024 IIBEC Interface • 9