ASTM C1193-00

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C 1193 – 00
Standard Guide for
Use of Joint Sealants
This standard is issued under the fixed designation C 1193; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 1.8 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
1.1 This guide describes the use of a cold liquid-applied
responsibility of the user of this standard to establish appro-
sealant for joint sealing applications. Including joints on
priate safety and health practices, and determine the applica-
buildings and related adjacent areas, such as plazas, decks, and
bility of regulatory limitations prior to use.
pavements for vehicular or pedestrian use, and types of
construction other than highways and airfield pavements and
2. Referenced Documents
bridges. Information in this guide is primarily applicable to a
2.1 ASTM Standards:
single and multi-component, cold liquid-applied joint sealant
C 510 Test Method for Staining and Color Change of
and secondarily to a precured sealant when used with a
Single- or Multicomponent Joint Sealants
properly prepared joint opening and substrate surfaces.
C 717 Terminology of Building Seals and Sealants
1.2 An elastomeric or non-elastomeric sealant described by
C 719 Test Method for Adhesion and Cohesion of Elasto-
thisguideshouldmeettherequirementsofSpecificationC 834,
meric Joint Sealants Under Cyclic Movement (Hockman
C 920, or C 1311.
Cycle)
1.3 This guide does not provide information or guidelines
C 792 Test Method for Effects of Heat Aging on Weight
for the use of a sealant in a structural sealant glazing applica-
Loss, Cracking and Chalking of Elastomeric Sealants
tion. Guide C 1401 should be consulted for this information.
C 794 Test Method for Adhesion-in-Peel of Elastomeric
Additionally, it also does not provide information or guidelines
Joint Sealants
fortheuseofasealantinaninsulatingglassunitedgesealused
C 834 Specification for Latex Sealants
inastructuralsealantglazingapplication.GuideC 1249should
C 919 Practice for Use of Sealants in Acoustical Applica-
be consulted for this information.
tions
1.4 Practice C 919 should be consulted for information and
C 920 Specification for Elastomeric Joint Sealants
guidelines for the use of a sealant in an application where an
C 1083 Test Method for WaterAbsorption of Cellular Elas-
acoustic joint seal is required.
tomeric Gaskets and Sealing Materials
1.5 This guide also does not provide information relative to
C 1087 Test Method for Determining Compatibility of
the numerous types of sealant that are available nor specific
Liquid-Applied Sealants with Accessories Used in Struc-
generic sealant properties, such as hardness, tack-free time, or
tural Glazing Systems
curing process, among others. Guide C 1299 should be con-
C 1135 Test Method for Determining Adhesion Properties
sulted for information on generally accepted comparative
of Structural sealants
values for the characteristics and properties of the more
C 1247 Test Method for Durability of Sealants Exposed to
common generic types of liquid-applied sealant.
Continuous Immersion in Liquids
1.6 The values stated in SI units are to be regarded as the
C 1248 Test Method for Staining of Porous Substrate by
standard. The values given in parenthesis are provided for
Joint Sealants
information only.
C 1249 Guide for Secondary Seal for Sealed Insulating
1.7 The Committee with jurisdiction for this standard is not
Glass Units for Structural Sealant Glazing applications
aware of any comparable standards published by other orga-
C 1253 Test Method for Determining the Outgassing Poten-
nizations.
tial of Sealant backing
C 1299 Guide for Use in Selection of Liquid-Applied Seal-
ants
This standard is under the jurisdiction of ASTM Committee C24 on Building
C 1311 Specification for Solvent Release Sealants
Seals and Sealants and is the direct responsibility of Subcommittee C24.10 on
C 1330 Specification for Cylindrical Sealant Backing for
Specifications, Guides and Practices.
Use with Cold Liquid-Applied Sealants
Current edition approved June 10, 2000. Published July 2000. Originally
published as C 1193–91. Last previous edition C 1193–91 (1999).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
C1193–00
C 1375 Guide for Substrates Used inTesting Building Seals its products and their proper use and installation. Considering
and Sealants the range of properties of commercially available sealants, the
C 1382 Guide for Determining TensileAdhesion Properties variety of joint designs possible, and the many conditions of
of Sealants When Used in Exterior Insulation and Finish use, the information contained herein is general in nature.
Systems (EIFS) Systems 4.3 To assist the user of the guide in locating specific
C 1401 Guide for Structural Sealant Glazing information, a detailed listing of guide numbered sections and
C 1442 Practice for Conducting Tests on Sealants Using their descriptors are included in Appendix X2.
Artificial Weathering Apparatus
5. General Considerations
C 1472 Guide for Calculating Movement and Other Effects
5.1 General—Proper selection and use of a sealant is
When Establishing Sealant Joint Width
fundamental to its ultimate performance, service life, and
D 2203 Test Method for Staining from Sealants
durability. A sealant joint subjected to movement and other
3. Terminology
similar performance factors should be designed for the particu-
lar application to avoid compromising its performance capa-
3.1 Definitions—RefertoTerminologyC 717fordefinitions
bility and causing failure (See 15). If not designed for the
of the following terms used in this guide: adhesive failure,
particular application, failure is a distinct probability. Equally
bicellular sealant backing, blooming, bond-breaker, bridge
important is the proper selection and use of other materials and
sealant joint, butt sealant joint, cell, cellular material, chalk,
products associated with sealant use. These include substrate
chalking, chemically curing sealant, closed cell, closed cell
cleaner, surface conditioner or primer, type of sealant backing
material, closed cell sealant backing, cohesive failure, compat-
material, bond-breaker, and joint filler, among others. The
ibility, compatible materials, compound, control joint, creep,
ability of a sealant installation to remain weather tight is
cure, cured, dirt pick-up, elastomeric, elongation, expansion
critically dependent on proper preparation, continuity, and
joint, fillet sealant joint, gasket, hydrostatic pressure, isolation
durability of the substrates to which the sealant will adhere,
joint, fluid migration, joint filler, laitance, latex sealant, modu-
lus, non-sag sealant, open cell, open cell material, open cell and compatibility of the sealant with the materials it will
contact, including the substrates. The proper application and
outgassing, sealant backing, primer, reversion, rundown, seal,
sealant, sealant backing, self-leveling sealant, shelf-life, sol- installationofthevariousmaterialsandproducts,followingthe
established joint design criteria, avoids premature deterioration
vent release sealant, shrinkage, silicone sealant, skin, structural
of the sealant joint. For a sealant joint that is difficult or
sealant, substrate, tooling, tooling time, weathertight, working
expensive to access (for example, tall buildings and certain
life (pot life).
roofs) a sealant should be selected that will have excellent
3.2 Definitions of Terms Specific to This Standard:
environmental weathering characteristics to minimize mainte-
3.2.1 durability, n—ability of a sealant joint and its parts to
nance. The following sections describe joint design guidelines
perform its required function over a period of time under the
and the properties and use of a sealant and its associated
influence of the environment.
materials.
3.2.2 durabilitylimit,n—pointatwhichlossofperformance
5.2 Durability—The durability of a sealant and a sealant
leads to the end of service life.
joint is related to many factors. For example, environmental
3.2.3 precured sealant, n—a preformed, factory cured, elas-
exposuretosolarradiation,ozone,heat-aging,andatmospheric
tomeric material.
contaminants can lessen sealant durability. Inadequate con-
3.2.4 premature deterioration, n—failure to achieve pre-
struction tolerances and improper sealant joint design for
dicted service life.
movement and other effects can contribute to sealant joint
3.2.5 service life, n—actual period of time during which no
failure, which is usually expressed as adhesive or cohesive
excessive expenditure is required for maintenance or repair of
failure of the sealant. Inadequate installation (for example,
a sealant joint.
where the sealant profile is inappropriate for movement, where
4. Significance and Use
substrates have not been properly cleaned and, if required,
4.1 This guide provides information and guidelines for primed, and the sealant inadequately tooled, among others) are
consideration by the designer or applicator of a joint seal. It common causes of failure. Conditions of exposure and design
explains the properties and functions of various materials, such (where, for example, a sealant joint is exposed to constant
as sealant, sealant backing, and primer, among others; and, wetting or to pedestrian or other traffic) can lessen sealant and
procedures such as, substrate cleaning and priming, and sealant joint durability. The type of sealant, its primary
installation of the components of a sealed joint. It presents polymer backbone, and the particular sealant formulation can
guidelines for the use and application of the various materials, also contribute to lessened durability, especially if a sealant is
design of a sealant joint for a specific application, and misused for an application or for conditions of use not
environmental conditions and effects that are known to detri- appropriate for it. Frequently, various combinations of envi-
mentally affect a sealant joint. The information and guidelines ronmental exposure and conditions of use occur which can
are also useful for those that supply accessories to the sealant resultinlesseneddurability.Forexample,dependingonsealant
industry and for those that install sealants and accessory type, joint movement combined with heat aging and cold
materials associated with sealant use. weather exposure or joint movement combined with heat aging
4.2 In addition to the design and installation data in this and moisture can result in failure. To enhance durability, it is
guide, consult the sealant manufacturer about applications for important that the sealant type is matched to the conditions of
C1193–00
use and exposure and that the sealant joint is of proper design almostalwaysdecreasetheperformancecapabilityofasealant.
forthoseconditionsofuseandexposure.Inanyevent,eventual Therefore, data sheet performance properties, if correct, gen-
replacement of a sealant that has reached its durability limit erally overstate the expected environmental and cyclic move-
must be planned for in the initial design and installation to ment performance of a sealant. With this in mind, a sealant
facilitate future remedial work.
joint design should always be performed with mitigating
design factors included in the design to account for movement-
5.2.1 Durability Testing—Presently, testing for sealant du-
during-cure (See 12.5).
rability consists of exposing small-scale sealant samples to
artificial weathering, without cycling movement, in a labora- 5.3 Adhesion—Obtaining and then maintaining long-term
tory accelerated weathering device to actinic radiation, mois-
adhesion of a sealant is the primary variable in a successful
ture, and heat according to Practice C 1442. Additionally,
installation. A sealant manufacturer will determine what is
environmental exposure at various locations (for example
necessary to achieve adequate adhesion to a particular sub-
Florida, Arizona, Texas, and certain northern latitudes) is also
strate, and if a primer or surface conditioner is necessary, by
conducted. Correlation of artificial weathering to environmen-
using laboratory test methods. In some applications, glass,
tal exposure is important to assess the relevance of laboratory
metal or other substrates may have coatings, surface treatments
test results to predicting sealant performance during environ-
or difficult-to-remove contaminants requiring special cleaning
mental use (1, 2). Laboratory tests to date indicate that at least
techniques or primers. Due to this surface variability, the
several thousand hours of artificial weathering exposure is
substrates should be sampled and tested by the sealant manu-
necessary to adequately predict a minimum level of environ-
facturer from actual production runs of the materials. Specifi-
mental performance. For example, if changes occur five times
cation C 920 requires a sealant to be rated as Use M, A, G, or
faster in a laboratory device than under environmental condi-
O. When listed by a sealant manufacturer it indicates that, in
tions (a typical average acceleration factor for a number of
general, the sealant has been found to adhere to and is suitable
materials), and the desired lifetime of a material is about five
for use with that substrate type. This is not necessarily a
years, as much as one year of artificial weathering may be
guarantee of adhesion. Samples of the actual substrate should
necessary to qualify a material for the application. The latest
always be tested for adhesion before use, since materials and
ASTM weathering standards recommend as a minimum expo-
finishes can be variable or products can change with time and
sure time that necessary to produce a substantial change in the
formulation from that as previously tested. Consideration
property of interest for the least stable material being evalu-
should also be given to identifying a sealant which, without the
ated. However, this may not be long enough to qualify a
use of primers if possible, will provide adequate adhesion.
material for the desired application. Environmental perfor-
5.3.1 Adhesion Testing—Adhesion of a sealant to a sub-
mance will vary with latitude. For example, a sealant used in
strate surface or another material or component is determined
Chicago will perform differently than the same sealant used in
using laboratory Test Methods C 794 and C 719. Adhesion
Florida for a similar application. Compass orientation also has
testing by a sealant manufacturer typically will be performed
an effect, with a northerly exposure sealant tending to last
after one day or 7 days of water immersion. For many
longer than a southerly. The incident solar radiation is a
applications this is not an adequate test exposure to predict
primary contributing factor, among others, to lessened durabil-
long term sealant joint performance. It is the user’s responsi-
ity. Other conditions being equal, the sealant in Chicago will in
bility to evaluate the water immersion condition of an adhesion
general perform for a longer time period than the same sealant
test conducted by the sealant manufacturer and determine if it
used in Florida.
is applicable to a particular use. If not, the user should obtain
5.2.1.1 The latest durability testing programs indicate that
appropriate data consistent with the intended application. In
artificialweatheringperformedconcurrentlywithmovementof
general, for most materials, sealant manufacturers have exten-
a sealant joint sample seems to more realistically predict
sive previous adhesion testing experience and can usually
sealant and sealant joint environmental performance (3, 4, 5,
indicate if their sealant will or will not adhere to a generic
6). Current ASTM laboratory test methods, that include a
material’s surface. Therefore, pre-qualification testing, prior to
durability component, such as C 719, do not provide an
specifying, is usually not necessary unless the manufacturer
adequate prediction of sealant long-term environmental perfor-
does not have relevant data for a particular material or if the
mance and therefore potential sealant and joint durability.
adhesion to a generic substrate varies significantly. Careful
5.2.1.2 TestmethodC 719evaluatesthemovementofanew
review of a sealant manufacturer’s data sheet is important,
sealant without the benefit of any aging or weathering and
since some only report extension or simple cyclic movement
thereby provides data only for an unaged sealant.
performance not including all the Test Method C 719 param-
5.2.1.3 The user of a sealant should realize that most eters and conditions. To monitor for any subsequent surface
manufacturer’s data sheets report laboratory testing data con- changes, consideration should be given to evaluating substrate
ducted in an idealized, as-cured state and not as a weathered adhesion on the installed substrates at the project site prior to
condition that represents how the sealant will actually appear beginningtheinstallationofthesealantandperiodicallyduring
and perform on a building. Additionally, the performance and the installation. Appendix X1 describes project site adhesion
other properties reported on many data sheets does not include testing methods.
movement during the curing process.
5.4 Compatibility—A sealant must be compatible with the
5.2.1.4 Almost all building sealant applications have materials and surfaces with which it will be in contact.
movement-during-cure. These natural movements during cure Occasionally, materials that are in close proximity, but not in
C1193–00
contact with the sealant, can have an effect on the installed complete and lasting removal of the stain is rarely achieved.
sealant. Incompatibility can cause, as a minimum, a discolora- Staining of non-porous surfaces can also be difficult to remove.
tion of the sealant or, at its extreme, sealant deterioration or Depending on the material, the type of fluid, and the type of
adhesion loss. Compatibility must never be assumed but environmental pollution or dirt pick-up, the staining may be
always established by a formal program of testing by the easily removed or can not be removed resulting in a permanent
sealant manufacturer, since there are no “always compatible” stain to the surface. Development of cleaning materials and
combinations of a sealant with other materials. A sealant methods must be a collaborative effort of the sealant manufac-
should be tested for compatibility with other sealants which it turer and the stained material manufacturer.
may contact and with materials and finishes it contacts or is in
5.5.1 Stain Testing—Laboratory testing for potential stain-
closeproximity.Materialsandfinishes,withtimeandexposure
ing of a porous substrate by a sealant can be performed using
to the ultraviolet component of sunlight, can exude or release
either Test Method D 2203, C 510, or C 1248. These test
plasticizers or other materials into a sealant, which can cause a
methods are typically used prior to sealant installation to test a
sealant to change color or lose adhesion. Also, these accesso-
specificsubstratematerialwithaparticularsealant.Itshouldbe
ries can have surface residues or contaminants from manufac-
realized that the tests are meant to be predictive based on
turing that can migrate into the sealant. A change of sealant
accelerated laboratory procedures that attempt to duplicate the
color is evidence of a potentially detrimental chemical reac-
natural environment. They are not always successful in dupli-
tion, and although adhesion may not be initially lost, the color
cating the natural environment and in identifying a potential
change could be predictive of a future loss of adhesion. Other
staining combination of sealant and substrate. Environmental
sealant characteristics that could also be affected by incompat-
testing for staining can also be performed using a mock-up of
ibility include the ability of a sealant to cure fully, its ultimate
the particular sealant and substrate exposed to the same
strength development, and its aesthetic qualities.
conditions as the end use. This procedure is usually lengthy,
5.4.1 Compatibility Testing—Materials or components that sometimes taking years before a judgement can be made as to
are nearby or touch the sealant should be tested for compat- staining potential. The sealant manufacturer should be con-
ibility using Test Method C 1087. This test is performed in the sultedforadvicesincetheyhaveahistoryoftheirproductsand
laboratory with prepared samples of substrate finishes, gaskets, staining potential with particular substrate materials. Test data
and various accessory materials, among others. Any color from a method such as C 1248 should be evaluated along with
change of the sealant after testing, is sufficient evidence to the sealant manufacturer’s recommendation and exposure data
cause additional evaluation for use of the candidate material or from older installations.
finish.This test is usually performed to prequalify a material or
5.6 Sealant Color Change—A sealant, in use, can change
component for use. In general, for most materials, sealant
color. A joint designer should be aware that developing a
manufacturers have extensive previous compatibility testing
specialcolorforaparticularapplicationmightbeinappropriate
experience and can usually indicate if their sealant is compat-
and additionally become a “throw away” cost. The surface
ible with a particular material. Therefore, pre-qualification
color of some sealants can change in as little as a few years
testing, prior to specifying, is usually not necessary unless the
depending on local environmental conditions. Color change
manufacturer does not have relevant data for a particular
can be caused by blooming, ultraviolet and visible radiation
material. An important aspect concerning compatibility is that
absorption,chalking,pollutantsintheatmosphere,dirtpick-up,
often a sealant or joint accessory is substituted at the last
cleaning solutions, and adjacent materials, among others (7-9).
minute as an “or equal” product. Products are not equal in
Blooming is the movement of components in a sealant to its
compatibility unless they are equally tested for compatibility.
surfacewheretheyattractdirtandatmosphericcontaminantsto
Therefore, if a sealant or an accessory material is substituted,
the surface of the sealant, changing its apparent color. Ultra-
the new combination should also be tested for compatibility.
violet and visible radiation absorption from the sun can
5.5 Substrate Staining—A sealant, depending on formula- permanently alter a sealant, depending on the type and quality
of pigment and stabilizer ingredients. Colors that seem to be
tion and the quality of its components, can cause staining of
adjacent substrate surfaces. Staining by a sealant is usually due mostaffectedbyultravioletandvisibleradiationabsorptionare
to fluid migration or rundown (7-11). Both porous and non- generally those created using organic coloring agents. Better
porous substrates are susceptible to this staining mechanism. color stability is achieved using inorganic colorants. The
Fluid from a sealant can migrate into the pores of a porous degree of color change due to this effect is variable depending
substrateandthenmigratetoitsexposedsurfaceadjacenttothe on the exposure of the sealant (e.g. northerly versus southerly
sealant. The fluid can then discolor the substrate surface or facing)andtheenvironment(southernversusnorthernlatitudes
become an attractant for environmental pollution or dirt inthesamehemisphere).Theformationofchalk(apowder)on
pick-up. This staining has been colloquially referred to as a sealant surface due to chalking can impart an apparent color
“clouding” due to its visual appearance. Fluid can also migrate change to the sealant’s surface by hiding the color of the
through the exposed surface of the sealant and then run down sealant. Most powders tend to be whitish in color, although a
onto adjacent porous or non-porous surfaces and become an color other than white can develop. Organic polymer based
attractant for environmental pollution or dirt pick-up. Staining sealants,astheyweather,canbeself-cleaningasrain-watercan
of porous substrates has proven to be difficult if not impossible wash away the surface chalk.Asealant can discolor due to the
to completely remove. Removal has usually been most suc- accumulation of atmospheric contaminants or dirt pick-up as
cessfully achieved using an appropriate poultice; however, the period of environmental exposure increases. Color change
C1193–00
caused by blooming, chalking, and the accumulation of atmo- and its adhesion to a substrate, as well as prolonged water
spheric contaminants or dirt pick-up, can usually be cleaned exposure described in 5.7.1. An appropriate practice for a
sealant joint subject to immersion is to design the joint profile
from the surface of the sealant using cleaning solutions and
procedures recommended by the sealant manufacturer. Build- as a continuous “bath tub plug.” This is a joint with tapered
ing facades are normally cleaned on a periodic basis. Cleaning sides or similar design to cause hydrostatic pressure to assist in
solutions used for other facade materials may have a deleteri- forming a compression seal, by pushing a sealant against the
ous affect on the color and other properties of a sealant and substrate.
should be verified as having no affect by a mock-up test
5.7.1 Liquid Immersion Resistance Testing—Test Method
program prior to application. Occasionally, a substrate material
C 1247 can be used to assess adhesion of a submerged sealant
that a sealant is adhered to, or another material that it is in
to a substrate. Water or other liquids can be used with this
incidental contact with, can cause a color change in the sealant
method to determine sealant performance. However, this
through migration of substrate or material components into the
method does not test the added influences of a constant stress
body of the sealant.
from hydrostatic pressure or an induced sealant stress from
5.6.1 Color Change Testing—Test Method C 1087 can be joint movement. For a particular application, this test may not
used to determine if sealant contact with a material will cause be an accelerated test depending on the temperature of the test
the sealant to discolor or lose adhesion.Test Method C 510 can liquid used in the application. The C 1247 test temperature is
50 °C (122 °F) and if that is also the application liquid
also be used; however, its value is limited due to the relatively
short time period for the test. Further, it would primarily be temperature, then the method may not be an accelerated test.
useful for porous substrates that may be discolored by compo- Also, most available immersion test data is based on clean
nents of the sealant that migrate into it.Test Method C 792 can water as the liquid. If a particular application has other than
be used to assess the chalking potential of a sealant; however, clean water as the liquid, the user should have the test
this test also has a relatively short time period for the test. It performed with the liquid in which the sealant will be
should be realized that the tests are meant to be predictive immersed.
based on accelerated laboratory procedures that attempt to
5.8 Environmental Influences:
duplicate the natural environment. They are not always suc-
5.8.1 Low Temperature—A low substrate temperature dur-
cessful in duplicating the natural environment and in identify-
ing installation generally decreases adhesion since the sealant
ing a potential color change combination of sealant and
surface wetting characteristic is reduced. Also, a low ambient
substrate. Accelerated laboratory tests that use a full spectrum
air temperature, depending on the sealant formulation and
of radiation, such as a xenon lamp, are most useful in
polymer backbone, can reduce the extrudability of a sealant
predicting color change. Environmental testing for color
and restrict its ability to flow into joint openings, thereby
changecanalsobeperformedusingamock-upoftheparticular
forming voids in the sealant. Frost, both visible and non-
sealant and substrate exposed to the same conditions as the end
visible, or ice may be present on a cold substrate surface
use. This procedure is usually lengthy, sometimes taking years
inhibiting adhesion. For these reasons, a sealant is more
before a judgement can be made as to a color change potential.
appropriately applied at an ambient air temperature above 4°C
The sealant manufacturer should be consulted for advice since
(40°F). If application is necessary when there is visible frost or
they have a history of their products and color change potential
ice on a substrate surface, the frost or ice must be removed by
with particular substrate and incidental contact materials. The
solvent wiping, evaporation of the solvent, and finally a dry
specifier or user can also confirm performance by observing
wipe. There is a risk of non-visible frost forming when
older installations.
evaporative cooling of a solvent, used to remove visible frost,
5.7 Liquid Immersion—Some sealant applications, for in-
causes the substrate temperature to fall below the dew point.A
stance a water retention structure or a waste water treatment
simple test, to determine the presence of non-visible frost on a
facility, require a sealant that can tolerate extended periods of
metal surface is to place a hand on the surface. Heat from ones
continuous immersion in water or other liquids (12, 13). Also,
hand will melt the frost, if it exists, and wet the surface. Also,
certain building joint applications, such as for plazas and other
for adhesion, the manufacturer of the sealant should be
horizontal surfaces, can subject a sealant to intermittent short
consulted regarding the extrudability and surface-wetting char-
or long term immersion in rain water or snow melt. Water
acteristics of the sealant as applicable to a particular substrate
immersion of a sealant is often associated with an accelerating
material.Alow temperature can be quite detrimental to a cured
influence on loss of adhesion of the sealant to a substrate and
sealant’sperformance.Alowtemperaturecanretardcureofthe
degradation of properties including sealant reversion. For other
sealant. Some sealants become stiff at a low temperature. If
than continuous water immersion situations, it is prudent to there is joint movement at a low temperature, a failure can
design joints that are not exposed to prolonged water immer-
result due to the reduced movement capability of the sealant
sion. These joints typically are under some stress from move- and the increased stress generated at the sealant adhesion
ment or other effects that, in combination with immersion, can
surface. If a low temperature will be a factor, then knowledge
result in a premature loss of adhesion. An important consider- of sealant performance at low temperature is fundamental as
ation in immersion situations is the development of a constant
well as knowledge of its brittle point (glass transition tempera-
dead load due to hydrostatic pressure on the sealant and its ture).ItshouldberealizedthatthelowtemperatureusedinTest
adhesion to a substrate. For such applications, an adhesion test Method C 719 is –26°C (–15°F) and may need to be lowered
should include the effect of hydrostatic pressure on the sealant depending on the particular low temperature application.
C1193–00
5.8.2 High Temperature—The sealant applicator should be ent, their existence is sometimes unknown until an adhesion
awarethatasealantthatismarginalwithrespecttohotweather failure occurs or testing is performed before installation.These
sag resistance may present a problem when working on an
conditions require special consideration and consultation with
application that has a solar exposure. A substrate surface, both the substrate and sealant manufacturers to determine
depending on color and thermal mass, can develop a high
suitable substrate preparation methods and which primer(s), if
surface temperature, which can exceed a sealant’s high tem- required, should be used before a sealant is applied. Often,
perature stability level. Such high temperatures can occur on
reliability of a selected cleaning and priming method can be
some dark colored surfaces in the summer. Knowledge of a predicted only by adhesion testing of a trial application at the
sealant’s sustained high temperature stability and the expected
project site on project materials. Other problematic conditions
in-use substrate surface temperature is fundamental to devel-
are sealant incompatibility with other chemical products on a
oping a durable sealant joint. Many organic sealants will start
porous material, such as concrete surface laitance, which
to deteriorate at 70 to 80 °C (158 to 176 °F). A sealant that
provides a weak substrate, and an adhesion-inhibiting form-
meets Specification C 920 is tested by method C 639 for its
release agent on a concrete surface. It is therefore essential that
flow (rheological or sag) properties at a temperature of 50 62
these materials be removed from a porous substrate surface.
°C (122 63.6 °F). Depending on a particular sealant and
Substrate porosity can also accelerate sealant adhesion loss
application this may not be adequate. Hot weather may also
when the substrate is wetted or immersed.Aprimer or surface
accelerate sealant cure time, resulting in a shortened working
conditioner (See 8) may improve sealant adhesion durability,
life and tooling time, while tack-free time will be reduced and
even if not required for adequate initial adhesion.
rain resistance accelerated. This is particularly helpful for a
6.2.2 Non-Porous—Stainless steel, lead-coated copper, and
water-based sealant, which is usually more susceptible to rain
anodized aluminum, factory-applied organic coatings, paints,
damage within the first few hours after application. A high
and glass are examples of materials that are considered
substrate temperature can increase bubble formation in a
non-porous. These materials are non-absorptive. A proprietary
sealant from outgassing of a sealant backing and thus must be
treatment or protective coating on a metal surface may inhibit
avoided (See 9.3).
sealant adhesion and should be removed completely. Where a
5.8.3 Moisture—Sealantinstallation,inunprotectedexterior
painted or coated metal is the substrate, the adhesion of the
locations, cannot be performed during or immediately after a
paintorcoatingtothesubstrateaswellasthecompatibilityand
rain and should not be performed when there is a threat or
bond of the sealant to the paint or coating is a matter of
knowledge of imminent rainfall. However, rainfall after appli-
concern. Also, non-porous materials are often of the type that
cation usually has no serious effect on most sealants if the
can’t be cut and reshaped at a project site. This becomes a
sealant has clearly formed a surface skin. Even a sealant with
concern when a joint opening, due to workmanship or other
a skin can be affected if there is forceful impingement of water,
considerations, has become smaller than the minimum accept-
prolonged flowing of water, or prolonged immersion of a
able width for the joint design. Typically, the joint opening
sealant joint. The sealant manufacturer should be consulted for
cannot be modified to make a wider joint to permit application
a specific recommendation when confronted with these or
of the planned sealant. When this occurs, either a different
similar situations. The moisture level in a porous substrate can
sealantwithgreatermovementcapabilityshouldbeinstalledor
also affect sealant adhesion, especially for joints that occur in
the joint design should be changed to a fillet or bridge type
horizontal surfaces such as plazas.
sealant joint if aesthetically acceptable (See 14.1.4.5 and 14.2).
6. Substrate
6.2.3 EIFS—An Exterior Insulation and Finish System
(EIFS) presents a porous substrate that may be acceptable for
6.1 General—Sealants have been developed to seal joints
sealant adhesion provided certain procedures are followed
between numerous substrate materials, the more common of
(14-16). Most manufacturers recommend adhering sealant
which are brick and concrete masonry, concrete, various
directly to the base coat and avoiding adhesion to the finish
metals, stone, and glass. Substrates are generally classified as
coat which can soften on exposure to moisture and lose
either porous or non-porous. Some substrates are generally
adhesion as the sealant extends and exerts a stress on the finish
more difficult to adhere sealant to than others. Surface charac-
coat. Typically, a sealant that has a low modulus should be
teristics vary considerably, and some substrates may not be
used. A low modulus sealant will have a lower stress at the
suitableforachievingajointsealunlesstreatedeithermechani-
sealant and substrate interface when the joint is in extension.
cally or chemically, or both. The substrate must be properly
Due to the difficulty that can be encountered in performing
prepared in all cases of use. The substrate must be clean, dry,
remedial work for an EIFS sealant joint, the selected sealant
sound, and free of loose particles, contaminants, foreign
matter, water-soluble material and frost and ice. should have very good environmental weathering characteris-
tics so that it will last for the useful lifetime of an EIFS
6.2 Types:
6.2.1 Porous—Materials representative of this type are installation.SinceanEIFSsystemiswater-based,ifitbecomes
saturatedwithrainwaterorsnowmelt,theadhesionofasealant
brick and concrete masonry, concrete, unpainted wood, some
building stones, and most cement-based materials. The classi- to an EIFS base coat can be lessened. Information on sealant
tensile adhesion properties when used with EIFS can be found
ficationofamaterialasporousisgenerallyrelatedtoitshaving
a pore structure in the body of the material. A water-repellent in Guide C 1382. EIFS can not tolerate grinding or cutting
treatment or coating on a porous substrate may inhibit sealant during sealant removal so it is a good candidate for use of a
adhesion. Since these coatings are not always visually appar- bridge type sealant joint or precured sealant, in a remedial
C1193–00
sealant application. This may be helpful since it does not Secondly, it stabilizes the substrate surface by filling pores and
require the removal of all the old or failed sealant but does strengthening weak areas. Lastly, it reduces capillary pressure
change the appearance of the joint seal. of moisture through a substrate surface. Some sealants require
the use of a primer on all substrates, while some require them
7. Cleaner
on only certain substrates or on none at all. The need for a
7.1 General—The quality of a cleaning method, cleaning
primer and the adhesion results achieved can vary, not only
solution, and cleaning cloths, among others, is as important as
with the substrate type, but also with the quality of the
the quality of a sealant. The surfaces to which a sealant will be
substrate. No consistent recommendation can be made regard-
applied must be properly cleaned. Any deleterious substances,
ing which substrate surfaces will require priming. Priming is
such as oil, grease, or powdery deposits that may interfere with
dependent on the sealant manufacturer, sealant type and
adhesion, must be removed completely.
formulation, substrate, and, in some instances, use and expo-
7.2 Procedure:
sure. With some sealants different primers are required for
7.2.1 Porous Substrate—Grinding, brushing, blowing off
different substrates. This poses a difficult application problem
with oil-free compressed air, and wiping with cloths are typical
when two different substrates require two different primers on
procedures that are used to clean a porous substrate. Solvents
opposite sides of a joint opening. This should be considered
are not generally used since they tend to dissolve contaminants when selecting a sealant. Many sealants require a primer for
and then re-deposit them in the pores of the material where
maximum adhesion to concrete and masonry surfaces. To
they become very difficult to remove. A porous substrate determine if a primer is required for a specific application,
should be free of dust, dirt and any other contaminant that
perform adhesion testing as described in 5.3.1.
would interfere with sealant adhesion. Concrete-based sub-
8.2 Materials—A primer or surface conditioner is a spe-
strates should have any laitance removed. Laitance is an
cially formulated liquid developed and recommended by the
unsound surface for sealant adhesion. Grinding or brushing
manufacturer of the sealant. A primer, if required, is normally
should be performed with materials and tools that will not
furnished by the sealant manufacturer and is typically formu-
leave deleterious substances (e.g. metal or fibrous particles)
lated for use only with the same manufacturer’s sealant. A
detrimental to sealant adhesion.
primer from one sealant manufacturer should never be used
7.2.2 Non-Porous Substrate—Degreasing solvents, such as
with a sealant from another manufacturer unless it has been
methyl ethyl ketone (MEK), toluene, xylene, acetone and
tested and approved by the manufacturer of the sealant with
mineral spirits have been used as cleaners. Many of these
whichitwillbeused.Somesealantmanufacturershaveseveral
solvents are regulated due to their potentially hazardous nature
primers that are used with their different sealants and with
and volatile organic compound (VOC) content. It is necessary
different substrates. Selection of a primer for use with a
to know the environment and safety provisions for a specific
particular sealant and substrate or substrate finish should be the
applicationbeforeaparticularsolventisselectedforevaluation
responsibility of the sealant manufacturer based on data
as a cleaner. Some solvents that may be considered appropriate
obtained from testing performed on submitted substrate finish
are effective degreasers but can leave a residue film on the
samples. As for a sealant, a primer must be stored and applied
cleaned surface, which should be removed. A residue film can
in accordance with the manufacturer’s recommendations and
be removed using a solution of fifty percent isopropyl alcohol
used within its stated shelf-life.
(IPA) and fifty percent water. However, this solution is not an
8.2.1 Color—It is not uncommon for a primer to be clear as
effective degreaser. A two step cleaning method can be used.
well as various shades of pink, red or yellow. The sealant
The first step is a solvent, which is a degreaser followed by the
manufacturer should establish an acceptable primer color, and
second step, which is a solution of IPA and water to remove
its range. A primer that does not conform should be discarded
any residue film. The sealant applicator should work closely
and replaced. A primer of questionable color or one that is
with the sealant manufacturer to develop a suitable cleaning
different from the manufacturer’s description should never be
procedure as determined by testing (See 16.4.4). When re-
used.
ceived at a shop or construction-site, and prior to use, a
8.2.2 Clarity—Clarity is often confused with color. A clear
cleaningagentshouldhaveitsqualityverified.Smallquantities
primer is free of particulate matter or settling and is not cloudy.
of organic and other contaminants, in the shipped cleaning
A primer may be water-white or various colors, such as, pink,
agent, can adversely affect adhesion of the sealant to a cleaned
red, yellow or some other color, and also clear. The sealant
surface. Additionally, containers for storage and use of a
manufacturer should establish the need for and degree of
cleaning agent must be clean. Cleaning cloths, rags, or paper
clarity, and the acceptability of solid material in a primer. A
wipes must also be free of contaminants and be lint free. Some
primer of questionable clarity or one that is different from the
commercially available disposable cloths or wipes contain
manufacturer’s description should never be used.
addit
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