ASTM C1373/C1373M-11(2017)
(Practice)Standard Practice for Determination of Thermal Resistance of Attic Insulation Systems Under Simulated Winter Conditions
Standard Practice for Determination of Thermal Resistance of Attic Insulation Systems Under Simulated Winter Conditions
SIGNIFICANCE AND USE
4.1 The thermal resistance of a ceiling system is used to characterize its steady-state thermal performance.
4.2 The thermal resistance of insulation is related to the density and thickness of the insulation. Test data on thermal resistance are obtained at a thickness and density representative of the end use applications. In addition, the thermal resistance of the insulation system will be different from that of the thermal insulation alone because of the system construction and materials.
4.3 This practice is needed because the in-service thermal resistance of some permeable attic insulations under winter conditions is different, lower or higher R, than that measured at or close to simulated room temperature conditions utilizing small-scale tests in which the insulation is sandwiched between two isothermal impermeable plates that have a temperature difference (ΔT) of 20 to 30°C [36 to 54°F]. When such insulation is installed in an attic, on top of a ceiling composed of normal building materials such as gypsum board or plywood, with an open top surface exposed to the attic air space, the thermal resistance under winter conditions with heat flow up and large temperature differences is significantly less because of additional heat transfer by natural convection. Fig. 1 illustrates the difference between results from small scale tests and tests under the conditions of this practice. See Ref (1-12) for discussions of this phenomenon.3
Note 1: A constant hot-side temperature (T, hot) is used for both tests and the temperature difference increases as the cold side temperature (T, cold) is decreased. See 5.1.6 for requirements on size of air space.
4.4 In normal use, the thickness of insulation products ranges from 75 mm [3 in.] to 500 mm [20 in.]. Installed densities will depend upon the product type, the installed thickness, the installation equipment used, the installation technique, and the geometry of the insulated space.
4.5 The onset of natural conve...
SCOPE
1.1 This practice presents a laboratory procedure to determine the thermal resistance of attic insulation systems under simulated steady-state winter conditions. The practice applies only to attic insulation systems that face an open attic air space.
1.2 The thermal resistance of the insulation is inferred from calculations based on measurements on a ceiling system consisting of components consistent with the system being studied. For example, such a system might consist of a gypsum board or plywood ceiling, wood ceiling joists, and attic insulation with its top exposed to an open air space. The temperature applied to the gypsum board or plywood shall be in the range of 18 to 24°C [64 to 75°F]. The air temperature above the insulation shall correspond to winter conditions and ranges from –46°C to 10°C [–51 to 50°F]. The gypsum board or plywood ceiling shall be sealed to prevent direct airflow between the warm and cold sides of the system.
1.3 This practice applies to a wide variety of loose-fill or blanket thermal insulation products including fibrous glass, rock/slag wool, or cellulosic fiber materials; granular types including vermiculite and perlite; pelletized products; and any other insulation material that is installed pneumatically or poured in place. The practice considers the effects on heat transfer of structures, specifically the ceiling joists, substrate, for example, gypsum board, air films, and possible facings, films, or other materials that are used in conjunction with the insulation.
1.4 This practice measures the thermal resistance of the attic/ceiling system in which the insulation material has been preconditioned according to the material Specifications C549, C665, C739, and C764.
1.5 The specimen preparation techniques outlined in this standard do not cover the characterization of loose-fill materials intended for enclosed applications.
1.6 This practice is be used to characterize mate...
General Information
Relations
Buy Standard
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C1373/C1373M − 11 (Reapproved 2017)
Standard Practice for
Determination of Thermal Resistance of Attic Insulation
Systems Under Simulated Winter Conditions
This standard is issued under the fixed designation C1373/C1373M; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.6 This practice is be used to characterize material behav-
iorundercontrolledsteady-statelaboratoryconditionsintended
1.1 This practice presents a laboratory procedure to deter-
to simulate actual temperature conditions of use. The practice
mine the thermal resistance of attic insulation systems under
does not simulate forced air flow conditions.
simulated steady-state winter conditions. The practice applies
onlytoatticinsulationsystemsthatfaceanopenatticairspace. 1.7 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. The values stated in
1.2 The thermal resistance of the insulation is inferred from
each system may not be exact equivalents; therefore, each
calculations based on measurements on a ceiling system
system shall be used independently of the other. Combining
consisting of components consistent with the system being
values from the two systems may result in non-conformance
studied. For example, such a system might consist of a gypsum
with the standard.
board or plywood ceiling, wood ceiling joists, and attic
1.7.1 All values shall be reported in both SI and inch-pound
insulation with its top exposed to an open air space. The
units unless specified otherwise by the client.
temperature applied to the gypsum board or plywood shall be
1.8 This standard does not purport to address all of the
in the range of 18 to 24°C [64 to 75°F]. The air temperature
safety concerns, if any, associated with its use. It is the
above the insulation shall correspond to winter conditions and
responsibility of the user of this standard to establish appro-
ranges from –46°C to 10°C [–51 to 50°F]. The gypsum board
priate safety and health practices and determine the applica-
or plywood ceiling shall be sealed to prevent direct airflow
bility of regulatory limitations prior to use.
between the warm and cold sides of the system.
1.9 This international standard was developed in accor-
1.3 This practice applies to a wide variety of loose-fill or
dance with internationally recognized principles on standard-
blanket thermal insulation products including fibrous glass,
ization established in the Decision on Principles for the
rock/slag wool, or cellulosic fiber materials; granular types
Development of International Standards, Guides and Recom-
including vermiculite and perlite; pelletized products; and any
mendations issued by the World Trade Organization Technical
other insulation material that is installed pneumatically or
Barriers to Trade (TBT) Committee.
poured in place. The practice considers the effects on heat
transfer of structures, specifically the ceiling joists, substrate,
2. Referenced Documents
for example, gypsum board, air films, and possible facings,
2.1 ASTM Standards:
films, or other materials that are used in conjunction with the
C167 Test Methods for Thickness and Density of Blanket or
insulation.
Batt Thermal Insulations
1.4 This practice measures the thermal resistance of the
C168 Terminology Relating to Thermal Insulation
attic/ceiling system in which the insulation material has been
C177 Test Method for Steady-State Heat Flux Measure-
preconditioned according to the material Specifications C549,
ments and Thermal Transmission Properties by Means of
C665, C739, and C764.
the Guarded-Hot-Plate Apparatus
1.5 The specimen preparation techniques outlined in this C518 Test Method for Steady-State Thermal Transmission
standard do not cover the characterization of loose-fill materi-
Properties by Means of the Heat Flow Meter Apparatus
als intended for enclosed applications. C520 Test Methods for Density of Granular Loose Fill
Insulations
C549 Specification for Perlite Loose Fill Insulation
This practice is under the jurisdiction of ASTM Committee C16 on Thermal
Insulation and is the direct responsibility of Subcommittee C16.30 on Thermal
Measurement. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2017. Published May 2017. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1998. Last previous edition approved in 2011 as C1373/C1373M – 11. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/C1373_C1373M-11R17. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1373/C1373M − 11 (2017)
C665 Specification for Mineral-Fiber Blanket Thermal Insu-
lation for Light Frame Construction and Manufactured
Housing
C687 Practice for Determination of Thermal Resistance of
Loose-Fill Building Insulation
C739 Specification for Cellulosic Fiber Loose-Fill Thermal
Insulation
C764 Specification for Mineral Fiber Loose-Fill Thermal
Insulation
C1045 Practice for Calculating Thermal Transmission Prop-
erties Under Steady-State Conditions
C1058 Practice for Selecting Temperatures for Evaluating
and Reporting Thermal Properties of Thermal Insulation
C1114 Test Method for Steady-State Thermal Transmission
Properties by Means of the Thin-Heater Apparatus
C1363 Test Method for Thermal Performance of Building
NOTE 1—Aconstant hot-side temperature (T, hot) is used for both tests
Materials and Envelope Assemblies by Means of a Hot
and the temperature difference increases as the cold side temperature (T,
Box Apparatus
cold) is decreased. See 5.1.6 for requirements on size of air space.
FIG. 1 Schematic of Thermal Resistance for a Permeable Attic
3. Terminology Insulation Under Simulated Winter Conditions (Heat Flow Up)
3.1 Definitions— Unless otherwise stated, the definitions
listed in Terminology C168 are applicable herein.
4.5 The onset of natural convection under winter conditions
is a function of specimen thickness for some materials. For
4. Significance and Use
purposes of this practice, the tests shall be carried out at
4.1 The thermal resistance of a ceiling system is used to
thicknesses at which the product is used.
characterize its steady-state thermal performance.
4.6 Since this practice simulates winter conditions, the heat
4.2 The thermal resistance of insulation is related to the
flow direction shall be vertically upwards.
density and thickness of the insulation. Test data on thermal
4.7 Specimensshallbepreparedinamannerconsistentwith
resistanceareobtainedatathicknessanddensityrepresentative
the intended installation procedure. Products for pneumatic
of the end use applications. In addition, the thermal resistance
installation shall be pneumatically-applied (blown), and prod-
of the insulation system will be different from that of the
ucts for pour-in-place installation shall be poured into place.
thermal insulation alone because of the system construction
See 5.2.
and materials.
5. Equipment
4.3 This practice is needed because the in-service thermal
resistance of some permeable attic insulations under winter
5.1 Thermal test apparatus used for this practice shall meet
conditions is different, lower or higher R, than that measured at
the following requirements:
or close to simulated room temperature conditions utilizing
5.1.1 Conformance to Standards—The apparatus shall con-
small-scaletestsinwhichtheinsulationissandwichedbetween
form to all requirements of the ASTM thermal test method
two isothermal impermeable plates that have a temperature
used, except as required by 5.1.2 – 5.1.6.
difference (∆T) of 20 to 30°C [36 to 54°F]. When such
5.1.2 Size—The apparatus shall be capable of testing speci-
insulation is installed in an attic, on top of a ceiling composed
mens at the thickness intended for product use. Length and
of normal building materials such as gypsum board or
width of the metering area shall be at least twice the spacing of
plywood, with an open top surface exposed to the attic air
the wood joists or four times the specimen thickness, which-
space, the thermal resistance under winter conditions with heat
ever is greater (see Fig. 2).
flow up and large temperature differences is significantly less
5.1.3 Temperature—The apparatus shall be capable of test-
because of additional heat transfer by natural convection. Fig.
ing with the hot side surface maintained between 18 and 24°C
1 illustrates the difference between results from small scale
[64 and 75°F], and with the cold side air temperature main-
tests and tests under the conditions of this practice. See Ref
tainednearthewinterconditionfortheparticularclimatebeing
(1-12) for discussions of this phenomenon.
simulated,whichrangesfrom–46to10°C[–51to50°F].Inthe
absence of specified temperatures, the ambient temperatures
4.4 In normal use, the thickness of insulation products
listed in Table 2 of C1058 on Temperatures for Thermal
ranges from 75 mm [3 in.] to 500 mm [20 in.]. Installed
Transmittance Evaluations is one source of test temperatures.
densities will depend upon the product type, the installed
thickness, the installation equipment used, the installation
NOTE 1—Only those with a hot ambient of 24°C [75°F] are applicable.
technique, and the geometry of the insulated space.
5.1.4 Humidity—The absolute humidity on both sides of the
test apparatus shall be maintained low enough to prevent
condensation within the specimen. See 6.9.6 of Test Method
The boldface numbers in parentheses refer to the list of references at the end of
this standard. C1363 for humidity requirements for the hot box methods, 6.6
C1373/C1373M − 11 (2017)
ing it with the blower operating. This practice dislodges any
pieces of old insulation that might be caught in the hose.
6. Sampling
6.1 A sample of material shall be selected from a lot
according to sampling plans given in the material
specifications, regulations, or other appropriate documents
when applicable. In the absence of such directions, material
from at least two randomly chosen packages shall be combined
in equal portions (mass) so as to combine materials as
uniformly as practicable.
6.2 The insulation material is preconditioned to a moisture
content in equilibrium with the laboratory conditions prior to
FIG. 2 Requirements on Dimensions of Test Specimen Metering
Area thespecimeninstallation.Preconditioningofmaterialsnotonly
ensures controlled installation conditions but reduces the time
required to condition the prepared specimen prior to thermal
testing. For conditioning requirements, see the applicable
of Test Method C177 for the guarded hot plate method, and
materials Specifications C520, C549, C665, C739, and C764.
7.10 of Test Method C518 for the heat flow meter apparatus.
5.1.5 Orientation and Direction of Heat Flow—The thermal
7. Specimen Preparation
test specimen shall be oriented horizontally with heat flow up.
7.1 General Instructions:
5.1.6 Thermal Test Specimen and Holder—The test assem-
7.1.1 Allspecimensshallbepreparedtoathicknessandunit
bly shall be sized to match the test apparatus and shall be made
area mass that are given for the label R-value specification of
of construction materials representative of the intended appli-
interest for the material under test.
cation. The substrate on which the insulation rests shall be
7.1.2 Specimens shall be prepared in a manner consistent
representative of the intended application, typically gypsum
with the intended installation procedure. All materials shall be
board. The substrate shall be sealed to prevent direct airflow
installed carefully using the manufacturer’s recommended
between the warm and cold sides of the system. Wood joists
installation practice. Batts shall be cut, as required, to fit the
also shall be included. The test assembly shall be constructed
available specimen holder. Products for pneumatic installation
suchthatthetopoftheinsulationisopentoanairspacehaving
shall be pneumatically-applied (blown), and products for
a minimum thickness of 150 mm [6 in.]. Test Methods C1363
pour-in-place installation shall be poured into the specimen
is preferred because of its ability to accommodate a large air
holder. See 7.2.2 for the density of pneumatically-installed
space. Other apparatuses that simulate in-service conditions
insulation. Other materials must be installed at the density
must meet the requirements of this practice, (for example,
suggested by the manufacturer.
modifications of Test Methods C177, C518,or C1114 with
7.1.3 The specimen holder shall represent typical attic
Practice C1045). In all cases, the size requirements given in
frame construction, wherever possible. This requires, as a
5.1.2 shall be met. Fig. 3 shows a schematic of an attic test
minimum, horizontal members representing the bottom chord
module that has been used for these types of tests. Other
of a truss system or rafter framing and an air-tight gypsum
configurations without the roof structure are acceptable as long
board or plywood bottom. The specimen holder shall be clean
as the minimum 150 mm [6 in.] air space is maintained.
and free of insulation residue prior to installation of the sample
5.2 Specimen Preparation Equipment:
insulation.
5.2.1 Blowing Apparatus—A blowing apparatus is required
NOTE 2—For commonly available loose-fill insulation, state and federal
when pneumatically-applied specimens are to be tested.
energy codes, ASTM material specifications and the Federal Trade
Choose the combination of hopper, blower, hose size and
Commission have identified those materials that shall apply a correction
length that is representative of common use for the application
for settling when determining thermal performance. It is beyond the scope
of the material to be tested. The following machine specifica-
of this practice to outline the procedures for this determination.
tions have been developed for use with mineral fiber and NOTE 3—Many factors can influence the characteristics of the loose-fill
insulation. These include blowing rate, machine adjustments, the size and
cellulosic materials.
length of the hose, and the angle and dimensions of the hose outlet in
5.2.1.1 A commercial blowing machine with a design ca-
relationtothespecimenholder.Trainedoperatorsarerequiredtoduplicate
pac
...
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: C1373/C1373M − 11 (Reapproved 2017)
Standard Practice for
Determination of Thermal Resistance of Attic Insulation
Systems Under Simulated Winter Conditions
This standard is issued under the fixed designation C1373/C1373M; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.6 This practice is be used to characterize material behav-
ior under controlled steady-state laboratory conditions intended
1.1 This practice presents a laboratory procedure to deter-
to simulate actual temperature conditions of use. The practice
mine the thermal resistance of attic insulation systems under
does not simulate forced air flow conditions.
simulated steady-state winter conditions. The practice applies
only to attic insulation systems that face an open attic air space. 1.7 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. The values stated in
1.2 The thermal resistance of the insulation is inferred from
each system may not be exact equivalents; therefore, each
calculations based on measurements on a ceiling system
system shall be used independently of the other. Combining
consisting of components consistent with the system being
values from the two systems may result in non-conformance
studied. For example, such a system might consist of a gypsum
with the standard.
board or plywood ceiling, wood ceiling joists, and attic
1.7.1 All values shall be reported in both SI and inch-pound
insulation with its top exposed to an open air space. The
units unless specified otherwise by the client.
temperature applied to the gypsum board or plywood shall be
1.8 This standard does not purport to address all of the
in the range of 18 to 24°C [64 to 75°F]. The air temperature
safety concerns, if any, associated with its use. It is the
above the insulation shall correspond to winter conditions and
responsibility of the user of this standard to establish appro-
ranges from –46°C to 10°C [–51 to 50°F]. The gypsum board
priate safety and health practices and determine the applica-
or plywood ceiling shall be sealed to prevent direct airflow
bility of regulatory limitations prior to use.
between the warm and cold sides of the system.
1.9 This international standard was developed in accor-
1.3 This practice applies to a wide variety of loose-fill or
dance with internationally recognized principles on standard-
blanket thermal insulation products including fibrous glass,
ization established in the Decision on Principles for the
rock/slag wool, or cellulosic fiber materials; granular types
Development of International Standards, Guides and Recom-
including vermiculite and perlite; pelletized products; and any
mendations issued by the World Trade Organization Technical
other insulation material that is installed pneumatically or
Barriers to Trade (TBT) Committee.
poured in place. The practice considers the effects on heat
transfer of structures, specifically the ceiling joists, substrate,
2. Referenced Documents
for example, gypsum board, air films, and possible facings,
2.1 ASTM Standards:
films, or other materials that are used in conjunction with the
C167 Test Methods for Thickness and Density of Blanket or
insulation.
Batt Thermal Insulations
1.4 This practice measures the thermal resistance of the
C168 Terminology Relating to Thermal Insulation
attic/ceiling system in which the insulation material has been
C177 Test Method for Steady-State Heat Flux Measure-
preconditioned according to the material Specifications C549,
ments and Thermal Transmission Properties by Means of
C665, C739, and C764.
the Guarded-Hot-Plate Apparatus
1.5 The specimen preparation techniques outlined in this
C518 Test Method for Steady-State Thermal Transmission
standard do not cover the characterization of loose-fill materi- Properties by Means of the Heat Flow Meter Apparatus
als intended for enclosed applications.
C520 Test Methods for Density of Granular Loose Fill
Insulations
C549 Specification for Perlite Loose Fill Insulation
This practice is under the jurisdiction of ASTM Committee C16 on Thermal
Insulation and is the direct responsibility of Subcommittee C16.30 on Thermal
Measurement. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2017. Published May 2017. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1998. Last previous edition approved in 2011 as C1373/C1373M – 11. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/C1373_C1373M-11R17. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1373/C1373M − 11 (2017)
C665 Specification for Mineral-Fiber Blanket Thermal Insu-
lation for Light Frame Construction and Manufactured
Housing
C687 Practice for Determination of Thermal Resistance of
Loose-Fill Building Insulation
C739 Specification for Cellulosic Fiber Loose-Fill Thermal
Insulation
C764 Specification for Mineral Fiber Loose-Fill Thermal
Insulation
C1045 Practice for Calculating Thermal Transmission Prop-
erties Under Steady-State Conditions
C1058 Practice for Selecting Temperatures for Evaluating
and Reporting Thermal Properties of Thermal Insulation
C1114 Test Method for Steady-State Thermal Transmission
Properties by Means of the Thin-Heater Apparatus
C1363 Test Method for Thermal Performance of Building
NOTE 1—A constant hot-side temperature (T, hot) is used for both tests
Materials and Envelope Assemblies by Means of a Hot
and the temperature difference increases as the cold side temperature (T,
Box Apparatus
cold) is decreased. See 5.1.6 for requirements on size of air space.
FIG. 1 Schematic of Thermal Resistance for a Permeable Attic
3. Terminology Insulation Under Simulated Winter Conditions (Heat Flow Up)
3.1 Definitions— Unless otherwise stated, the definitions
listed in Terminology C168 are applicable herein.
4.5 The onset of natural convection under winter conditions
is a function of specimen thickness for some materials. For
4. Significance and Use
purposes of this practice, the tests shall be carried out at
4.1 The thermal resistance of a ceiling system is used to thicknesses at which the product is used.
characterize its steady-state thermal performance.
4.6 Since this practice simulates winter conditions, the heat
4.2 The thermal resistance of insulation is related to the flow direction shall be vertically upwards.
density and thickness of the insulation. Test data on thermal
4.7 Specimens shall be prepared in a manner consistent with
resistance are obtained at a thickness and density representative
the intended installation procedure. Products for pneumatic
of the end use applications. In addition, the thermal resistance
installation shall be pneumatically-applied (blown), and prod-
of the insulation system will be different from that of the
ucts for pour-in-place installation shall be poured into place.
thermal insulation alone because of the system construction
See 5.2.
and materials.
5. Equipment
4.3 This practice is needed because the in-service thermal
resistance of some permeable attic insulations under winter
5.1 Thermal test apparatus used for this practice shall meet
conditions is different, lower or higher R, than that measured at
the following requirements:
or close to simulated room temperature conditions utilizing
5.1.1 Conformance to Standards—The apparatus shall con-
small-scale tests in which the insulation is sandwiched between
form to all requirements of the ASTM thermal test method
two isothermal impermeable plates that have a temperature
used, except as required by 5.1.2 – 5.1.6.
difference (ΔT) of 20 to 30°C [36 to 54°F]. When such
5.1.2 Size—The apparatus shall be capable of testing speci-
insulation is installed in an attic, on top of a ceiling composed
mens at the thickness intended for product use. Length and
of normal building materials such as gypsum board or
width of the metering area shall be at least twice the spacing of
plywood, with an open top surface exposed to the attic air
the wood joists or four times the specimen thickness, which-
space, the thermal resistance under winter conditions with heat
ever is greater (see Fig. 2).
flow up and large temperature differences is significantly less
5.1.3 Temperature—The apparatus shall be capable of test-
because of additional heat transfer by natural convection. Fig.
ing with the hot side surface maintained between 18 and 24°C
1 illustrates the difference between results from small scale
[64 and 75°F], and with the cold side air temperature main-
tests and tests under the conditions of this practice. See Ref
tained near the winter condition for the particular climate being
(1-12) for discussions of this phenomenon.
simulated, which ranges from –46 to 10°C [–51 to 50°F]. In the
absence of specified temperatures, the ambient temperatures
4.4 In normal use, the thickness of insulation products
listed in Table 2 of C1058 on Temperatures for Thermal
ranges from 75 mm [3 in.] to 500 mm [20 in.]. Installed
Transmittance Evaluations is one source of test temperatures.
densities will depend upon the product type, the installed
thickness, the installation equipment used, the installation
NOTE 1—Only those with a hot ambient of 24°C [75°F] are applicable.
technique, and the geometry of the insulated space.
5.1.4 Humidity—The absolute humidity on both sides of the
test apparatus shall be maintained low enough to prevent
3 condensation within the specimen. See 6.9.6 of Test Method
The boldface numbers in parentheses refer to the list of references at the end of
this standard. C1363 for humidity requirements for the hot box methods, 6.6
C1373/C1373M − 11 (2017)
ing it with the blower operating. This practice dislodges any
pieces of old insulation that might be caught in the hose.
6. Sampling
6.1 A sample of material shall be selected from a lot
according to sampling plans given in the material
specifications, regulations, or other appropriate documents
when applicable. In the absence of such directions, material
from at least two randomly chosen packages shall be combined
in equal portions (mass) so as to combine materials as
uniformly as practicable.
6.2 The insulation material is preconditioned to a moisture
content in equilibrium with the laboratory conditions prior to
FIG. 2 Requirements on Dimensions of Test Specimen Metering
Area the specimen installation. Preconditioning of materials not only
ensures controlled installation conditions but reduces the time
required to condition the prepared specimen prior to thermal
testing. For conditioning requirements, see the applicable
of Test Method C177 for the guarded hot plate method, and
materials Specifications C520, C549, C665, C739, and C764.
7.10 of Test Method C518 for the heat flow meter apparatus.
5.1.5 Orientation and Direction of Heat Flow—The thermal
7. Specimen Preparation
test specimen shall be oriented horizontally with heat flow up.
7.1 General Instructions:
5.1.6 Thermal Test Specimen and Holder—The test assem-
7.1.1 All specimens shall be prepared to a thickness and unit
bly shall be sized to match the test apparatus and shall be made
area mass that are given for the label R-value specification of
of construction materials representative of the intended appli-
interest for the material under test.
cation. The substrate on which the insulation rests shall be
7.1.2 Specimens shall be prepared in a manner consistent
representative of the intended application, typically gypsum
with the intended installation procedure. All materials shall be
board. The substrate shall be sealed to prevent direct airflow
installed carefully using the manufacturer’s recommended
between the warm and cold sides of the system. Wood joists
installation practice. Batts shall be cut, as required, to fit the
also shall be included. The test assembly shall be constructed
available specimen holder. Products for pneumatic installation
such that the top of the insulation is open to an air space having
shall be pneumatically-applied (blown), and products for
a minimum thickness of 150 mm [6 in.]. Test Methods C1363
pour-in-place installation shall be poured into the specimen
is preferred because of its ability to accommodate a large air
holder. See 7.2.2 for the density of pneumatically-installed
space. Other apparatuses that simulate in-service conditions
insulation. Other materials must be installed at the density
must meet the requirements of this practice, (for example,
suggested by the manufacturer.
modifications of Test Methods C177, C518, or C1114 with
7.1.3 The specimen holder shall represent typical attic
Practice C1045). In all cases, the size requirements given in
frame construction, wherever possible. This requires, as a
5.1.2 shall be met. Fig. 3 shows a schematic of an attic test
minimum, horizontal members representing the bottom chord
module that has been used for these types of tests. Other
of a truss system or rafter framing and an air-tight gypsum
configurations without the roof structure are acceptable as long
board or plywood bottom. The specimen holder shall be clean
as the minimum 150 mm [6 in.] air space is maintained.
and free of insulation residue prior to installation of the sample
5.2 Specimen Preparation Equipment:
insulation.
5.2.1 Blowing Apparatus—A blowing apparatus is required
NOTE 2—For commonly available loose-fill insulation, state and federal
when pneumatically-applied specimens are to be tested.
energy codes, ASTM material specifications and the Federal Trade
Choose the combination of hopper, blower, hose size and
Commission have identified those materials that shall apply a correction
length that is representative of common use for the application
for settling when determining thermal performance. It is beyond the scope
of the material to be tested. The following machine specifica-
of this practice to outline the procedures for this determination.
tions have been developed for use with mineral fiber and NOTE 3—Many factors can influence the characteristics of the loose-fill
insulation. These include blowing rate, machine adjustments, the size and
cellulosic materials.
length of the hose, and the angle and dimensions of the hose outlet in
5.2.1.1 A commercial blowing machine with a design ca-
relation to the specimen holder. Trained operators are required to duplicate
pacity for deliveri
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1373/C1373M − 11 C1373/C1373M − 11 (Reapproved 2017)
Standard Practice for
Determination of Thermal Resistance of Attic Insulation
Systems Under Simulated Winter Conditions
This standard is issued under the fixed designation C1373/C1373M; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This practice presents a laboratory procedure to determine the thermal resistance of attic insulation systems under simulated
steady-state winter conditions. The practice applies only to attic insulation systems that face an open attic air space.
1.2 The thermal resistance of the insulation is inferred from calculations based on measurements on a ceiling system consisting
of components consistent with the system being studied. For example, such a system might consist of a gypsum board or plywood
ceiling, wood ceiling joists, and attic insulation with its top exposed to an open air space. The temperature applied to the gypsum
board or plywood shall be in the range of 18 to 24°C [64 to 75°F]. The air temperature above the insulation shall correspond to
winter conditions and ranges from –46°C to 10°C [–51 to 50°F]. The gypsum board or plywood ceiling shall be sealed to prevent
direct airflow between the warm and cold sides of the system.
1.3 This practice applies to a wide variety of loose-fill or blanket thermal insulation products including fibrous glass, rock/slag
wool, or cellulosic fiber materials; granular types including vermiculite and perlite; pelletized products; and any other insulation
material that is installed pneumatically or poured in place. The practice considers the effects on heat transfer of structures,
specifically the ceiling joists, substrate, for example, gypsum board, air films, and possible facings, films, or other materials that
are used in conjunction with the insulation.
1.4 This practice measures the thermal resistance of the attic/ceiling system in which the insulation material has been
preconditioned according to the material Specifications C549, C665, C739, and C764.
1.5 The specimen preparation techniques outlined in this standard do not cover the characterization of loose-fill materials
intended for enclosed applications.
1.6 This practice is be used to characterize material behavior under controlled steady-state laboratory conditions intended to
simulate actual temperature conditions of use. The practice does not simulate forced air flow conditions.
1.7 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
1.7.1 All values shall be reported in both SI and inch-pound units unless specified otherwise by the client.
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
1.9 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C167 Test Methods for Thickness and Density of Blanket or Batt Thermal Insulations
C168 Terminology Relating to Thermal Insulation
This practice is under the jurisdiction of ASTM Committee C16 on Thermal Insulation and is the direct responsibility of Subcommittee C16.30 on Thermal Measurement.
Current edition approved Nov. 1, 2011May 1, 2017. Published December 2011.May 2017. Originally approved in 1998. Last previous edition approved in 20032011 as
C1373C1373/C1373M – 11.–03. DOI: 10.1520/C1373_C1373M-11.10.1520/C1373_C1373M-11R17.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1373/C1373M − 11 (2017)
NOTE 1—A constant hot-side temperature (T, hot) is used for both tests and the temperature difference increases as the cold side temperature (T, cold)
is decreased. See 5.1.6 for requirements on size of air space.
FIG. 1 Schematic of Thermal Resistance for a Permeable Attic Insulation Under Simulated Winter Conditions (Heat Flow Up)
C177 Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the
Guarded-Hot-Plate Apparatus
C518 Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus
C520 Test Methods for Density of Granular Loose Fill Insulations
C549 Specification for Perlite Loose Fill Insulation
C665 Specification for Mineral-Fiber Blanket Thermal Insulation for Light Frame Construction and Manufactured Housing
C687 Practice for Determination of Thermal Resistance of Loose-Fill Building Insulation
C739 Specification for Cellulosic Fiber Loose-Fill Thermal Insulation
C764 Specification for Mineral Fiber Loose-Fill Thermal Insulation
C1045 Practice for Calculating Thermal Transmission Properties Under Steady-State Conditions
C1058 Practice for Selecting Temperatures for Evaluating and Reporting Thermal Properties of Thermal Insulation
C1114 Test Method for Steady-State Thermal Transmission Properties by Means of the Thin-Heater Apparatus
C1363 Test Method for Thermal Performance of Building Materials and Envelope Assemblies by Means of a Hot Box Apparatus
3. Terminology
3.1 Definitions— Unless otherwise stated, the definitions listed in Terminology C168 are applicable herein.
4. Significance and Use
4.1 The thermal resistance of a ceiling system is used to characterize its steady-state thermal performance.
4.2 The thermal resistance of insulation is related to the density and thickness of the insulation. Test data on thermal resistance
are obtained at a thickness and density representative of the end use applications. In addition, the thermal resistance of the
insulation system will be different from that of the thermal insulation alone because of the system construction and materials.
4.3 This practice is needed because the in-service thermal resistance of some permeable attic insulations under winter conditions
is different, lower or higher R, than that measured at or close to simulated room temperature conditions utilizing small-scale tests
in which the insulation is sandwiched between two isothermal impermeable plates that have a temperature difference (ΔT) of 20
to 30°C [36 to 54°F]. When such insulation is installed in an attic, on top of a ceiling composed of normal building materials such
as gypsum board or plywood, with an open top surface exposed to the attic air space, the thermal resistance under winter conditions
with heat flow up and large temperature differences is significantly less because of additional heat transfer by natural convection.
Fig. 1 illustrates the difference between results from small scale tests and tests under the conditions of this practice. See Ref (1-12)
for discussions of this phenomenon.
4.4 In normal use, the thickness of insulation products ranges from 75 mm [3 in.] to 500 mm [20 in.]. Installed densities will
depend upon the product type, the installed thickness, the installation equipment used, the installation technique, and the geometry
of the insulated space.
4.5 The onset of natural convection under winter conditions is a function of specimen thickness for some materials. For
purposes of this practice, the tests shall be carried out at thicknesses at which the product is used.
The boldface numbers in parentheses refer to the list of references at the end of this standard.
C1373/C1373M − 11 (2017)
FIG. 2 Requirements on Dimensions of Test Specimen Metering Area
4.6 Since this practice simulates winter conditions, the heat flow direction shall be vertically upwards.
4.7 Specimens shall be prepared in a manner consistent with the intended installation procedure. Products for pneumatic
installation shall be pneumatically-applied (blown), and products for pour-in-place installation shall be poured into place. See 5.2.
5. Equipment
5.1 Thermal test apparatus used for this practice shall meet the following requirements:
5.1.1 Conformance to Standards—The apparatus shall conform to all requirements of the ASTM thermal test method used,
except as required by 5.1.2 – 5.1.6.
5.1.2 Size—The apparatus shall be capable of testing specimens at the thickness intended for product use. Length and width of
the metering area shall be at least twice the spacing of the wood joists or four times the specimen thickness, whichever is greater
(see Fig. 2).
5.1.3 Temperature—The apparatus shall be capable of testing with the hot side surface maintained between 18 and 24°C [64
and 75°F], and with the cold side air temperature maintained near the winter condition for the particular climate being simulated,
which ranges from –46 to 10°C [–51 to 50°F]. In the absence of specified temperatures, the ambient temperatures listed in Table
2 of C1058 on Temperatures for Thermal Transmittance Evaluations is one source of test temperatures.
NOTE 1—Only those with a hot ambient of 24°C [75°F] are applicable.
5.1.4 Humidity—The absolute humidity on both sides of the test apparatus shall be maintained low enough to prevent
condensation within the specimen. See 6.9.6 of Test Method C1363 for humidity requirements for the hot box methods, 6.6 of
Test Method C177 for the guarded hot plate method, and 7.10 of Test Method C518 for the heat flow meter apparatus.
5.1.5 Orientation and Direction of Heat Flow—The thermal test specimen shall be oriented horizontally with heat flow up.
5.1.6 Thermal Test Specimen and Holder—The test assembly shall be sized to match the test apparatus and shall be made of
construction materials representative of the intended application. The substrate on which the insulation rests shall be representative
of the intended application, typically gypsum board. The substrate shall be sealed to prevent direct airflow between the warm and
cold sides of the system. Wood joists also shall be included. The test assembly shall be constructed such that the top of the
insulation is open to an air space having a minimum thickness of 150 mm [6 in.]. Test Methods C1363 is preferred because of its
ability to accommodate a large air space. Other apparatuses that simulate in-service conditions must meet the requirements of this
practice, (for example, modifications of Test Methods C177, C518, or C1114 with Practice C1045). In all cases, the size
requirements given in 5.1.2 shall be met. Fig. 3 shows a schematic of an attic test module that has been used for these types of
tests. Other configurations without the roof structure are acceptable as long as the minimum 150 mm [6 in.] air space is maintained.
5.2 Specimen Preparation Equipment:
5.2.1 Blowing Apparatus—A blowing apparatus is required when pneumatically-applied specimens are to be tested. Choose the
combination of hopper, blower, hose size and length that is representative of common use for the application of the material to be
tested. The following machine specifications have been developed for use with mineral fiber and cellulosic materials.
5.2.1.1 A commercial blowing machine with a design capacity for delivering the subject material at a rate recommended by the
insulation manufacturer shall be used. The machine must utilize 46 m [150 ft] of flexible, internally corrugated blowing hose with
an appropriate sized diameter as specified by the machine manufacturer. At least 30 m [100 ft] of the hose must be elevated between
3 and 6 m [10 and 20 ft] above the blowing machine to simulate typical installation configuration. The hose must have no more
than eight 90° bends and no bends less than 1.2 m [4 ft] radius. It is good practice to clean the hose periodically by mechanically
agitating it with the blower operating. This practice dislodges any pieces of old insulation that might be caught in the hose.
C1373/C1373M − 11 (2017)
FIG. 3 Schematic of Attic Test Module and Large Scale Climate Simulator Used for Tests on Attic Insulation Under Simulated Winter
Conditions
6. Sampling
6.1 A sample of material shall be selected from a lot according to sampling plans given in the material specifications,
regulations, or other appropriate documents when applicable. In the absence of such directions, material from at least two randomly
chosen packages shall be combined in equal portions (mass) so as to combine materials as uniformly as practicable.
6.2 The insulation material is preconditioned to a moisture content in equilibrium with the laboratory conditions prior to the
specimen installation. Preconditioning of materials not only ensures controlled installation conditions but reduces the time required
to condition the prepared specimen prior to thermal testing. For conditioning requirements, see the applicable materials
Specifications C520, C549, C665, C739, and C764.
7. Specimen Preparation
7.1 General Instructions:
7.1.1 All specimens shall be prepared to a thickness and unit area mass that are given for the label R-value specification of
interest for the material under test.
7.1.2 Specimens shall be prepared in a manner consistent with the intended installation procedure. All materials shall be
installed carefully using the manufacturer’s recommended installation practice. Batts shall be cut, as required, to fit the available
specimen holder. Products for pneumatic installation shall be pneumatically-applied (blown), and products for pour-in-place
installation shall be poured into the specimen holder. See 7.2.2 for the density of pneumatically-installed insulation. Other mat
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.