ASTM E1423-21

Standard Practice for Determining Steady State Thermal Transmittance of Fenestration Systems

SIGNIFICANCE AND USE
4.1 This practice details the test specimen sizes and test conditions, namely, the room-side and weather-side air temperatures, and the surface heat transfer coefficients for both sides of the test specimen, when testing fenestration products in accordance with Test Method C1199.  
4.2 The thermal transmittance and conductance of a specimen are affected by its size and three-dimensional geometry. Tests should therefore be conducted using the specimen sizes recommended in 5.1. Should the specimen size differ from those given in 5.1, the actual size shall be reported in the test report.  
4.3 Many factors can affect the thermal performance of a fenestration system, including deflections of sealed glazing units. Care should be exercised to maintain the original physical condition of the fenestration system and while installing it in the surround panel.  
4.4 The thermal transmittance and conductance results obtained do not, and are not intended, to reflect performances expected from field installations since they do not account for solar radiation and air leakage effects. The thermal transmittance and conductance results are taken from specified laboratory conditions and are to be used only for fenestration product comparisons and as input to thermal performance analyses that also include solar and air leakage effects.
SCOPE
1.1 This practice covers standard test specimen sizes and test conditions as well as the calculation and presentation of the thermal transmittance and conductance data measured in accordance with Test Method C1199. The standard sizes and conditions are to be used for fenestration product comparison purposes. The specifier may choose other sizes and conditions for product development or research purposes.  
1.2 This practice deals with the determination of the thermal properties of a fenestration system installed vertically without the influences of solar heat gain and air leakage effects.
Note 1: To determine air leakage effects of fenestration systems, Test Method E283/E283M or E1424 should be referenced.
Note 2: See Appendix X1 regarding garage doors and rolling doors.  
1.3 This practice specifies the procedure for determining the standardized thermal transmittance of a fenestration test specimen using specified values of the room-side and weather-side surface heat transfer coefficients, hh and hc, respectively.  
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 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.

General Information

• Status: Published
• Publication Date: 31-Jul-2021
• ICS: 91.060.50 - Doors and windows
• ICS: 91.120.10 - Thermal insulation of buildings
• Technical Committee: E06 - Performance of Buildings
• Drafting Committee: E06.51 - Performance of Windows, Doors, Skylights and Curtain Walls

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: E1423 − 21
Standard Practice for
Determining Steady State Thermal Transmittance of
1
Fenestration Systems
This standard is issued under the fixed designation E1423; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2
2.1 ASTM Standards:
1.1 This practice covers standard test specimen sizes and
C168Terminology Relating to Thermal Insulation
testconditionsaswellasthecalculationandpresentationofthe
C1199TestMethodforMeasuringtheSteady-StateThermal
thermal transmittance and conductance data measured in ac-
Transmittance of Fenestration Systems Using Hot Box
cordance with Test Method C1199. The standard sizes and
Methods
conditions are to be used for fenestration product comparison
C1363Test Method for Thermal Performance of Building
purposes. The specifier may choose other sizes and conditions
Materials and Envelope Assemblies by Means of a Hot
for product development or research purposes.
Box Apparatus
1.2 Thispracticedealswiththedeterminationofthethermal
E283/E283MTest Method for Determining Rate of Air
properties of a fenestration system installed vertically without
Leakage Through Exterior Windows, Skylights, Curtain
the influences of solar heat gain and air leakage effects.
Walls, and Doors Under Specified Pressure Differences
Across the Specimen
NOTE 1—To determine air leakage effects of fenestration systems, Test
E631Terminology of Building Constructions
Method E283/E283M or E1424 should be referenced.
E783Test Method for Field Measurement of Air Leakage
NOTE 2—See Appendix X1 regarding garage doors and rolling doors.
Through Installed Exterior Windows and Doors
1.3 Thispracticespecifiestheprocedurefordeterminingthe
E1424TestMethodforDeterminingtheRateofAirLeakage
standardized thermal transmittance of a fenestration test speci-
Through Exterior Windows, Curtain Walls, and Doors
men using specified values of the room-side and weather-side
Under Specified Pressure and Temperature Differences
surface heat transfer coefficients, h and h , respectively.
Across the Specimen
h c
2.2 Other Documents:
1.4 The values stated in SI units are to be regarded as
ANSI/DASMA105Test Method forThermalTransmittance
standard. The values given in parentheses after SI units are
3
and Air Infiltration of Garage Doors and Rolling Doors
providedforinformationonlyandarenotconsideredstandard.
NFRC 102Procedure for Measuring the Steady-State Ther-
1.5 This standard does not purport to address all of the 4
mal Transmittance of Fenestration Systems
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Terminology
priate safety, health, and environmental practices and deter-
3.1 Definitions—Definitions and terms are in accordance
mine the applicability of regulatory limitations prior to use.
with Terminology E631 and C168, from which the following
1.6 This international standard was developed in accor-
have been selected and modified to apply specifically to
dance with internationally recognized principles on standard-
fenestration systems. See Fig. 1 and Fig. 2 for variable
ization established in the Decision on Principles for the
identification. (For further information on definitions and
Development of International Standards, Guides and Recom-
procedures, see Appendix X2 or Test Method C1199.)
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
1
This practice is under the jurisdiction of ASTM Committee E06 on Perfor- Standards volume information, refer to the standard’s Document Summary page on
mance of Buildings and is the direct responsibility of Subcommittee E06.51 on the ASTM website.
3
Performance of Windows, Doors, Skylights and Curtain Walls. Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
Current edition approved Aug. 1, 2021. Published August 2021. Originally 4th Floor, New York, NY 10036, http://www.ansi.org.
4
approved in 1991. Last previous edition approved in 2014 as E1423–14. DOI: Available from National Fenestration Rating Council (NFRC), 6305 Ivy Ln.,
10.1520/E1423-21. Suite 140, Greenbelt, MD 20770, http://www.nfrc.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
...

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: E1423 − 14 E1423 − 21
Standard Practice for
Determining Steady State Thermal Transmittance of
1
Fenestration Systems
This standard is issued under the fixed designation E1423; 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 covers standard test specimen sizes and test conditions as well as the calculation and presentation of the thermal
transmittance and conductance data measured in accordance with Test Method C1199. The standard sizes and conditions are to be
used for fenestration product comparison purposes. The specifier may choose other sizes and conditions for product development
or research purposes.
1.2 This practice deals with the determination of the thermal properties of a fenestration system installed vertically without the
influences of solar heat gain and air leakage effects.
NOTE 1—To determine air leakage effects of fenestration systems, Test Method E283E283/E283M or E1424 should be referenced.
NOTE 2—See Appendix Appendix X1 regarding garage doors and rolling doors.
1.3 This practice specifies the procedure for determining the standardized thermal transmittance of a fenestration test specimen
using specified values of the room-side and weather-side surface heat transfer coefficients, h and h , respectively.
h c
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.after
SI units are provided for information only and are not considered standard.
1.5 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.6 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
2.1 ASTM Standards:
C168 Terminology Relating to Thermal Insulation
C1199 Test Method for Measuring the Steady-State Thermal Transmittance of Fenestration Systems Using Hot Box Methods
1
This guidepractice is under the jurisdiction of ASTM Committee E06 on Performance of Buildings and is the direct responsibility of Subcommittee E06.51 on
Performance of Windows, Doors, Skylights and Curtain Walls.
Current edition approved April 1, 2014Aug. 1, 2021. Published May 2014August 2021. Originally approved in 1991. Last previous edition approved in 20062014 as
E1423 – 06.E1423 – 14. DOI: 10.1520/E1423-14.10.1520/E1423-21.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’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
1

---------------------- Page: 1 ----------------------
E1423 − 21
C1363 Test Method for Thermal Performance of Building Materials and Envelope Assemblies by Means of a Hot Box Apparatus
E283E283/E283M Test Method for Determining Rate of Air Leakage Through Exterior Windows, Skylights, Curtain Walls, and
Doors Under Specified Pressure Differences Across the Specimen
E631 Terminology of Building Constructions
E783 Test Method for Field Measurement of Air Leakage Through Installed Exterior Windows and Doors
E1424 Test Method for Determining the Rate of Air Leakage Through Exterior Windows, Curtain Walls, and Doors Under
Specified Pressure and Temperature Differences Across the Specimen
2.2 Other Documents:
3
ANSI/DASMA 105-1998105 Test Method for Thermal Transmittance and Air Infiltration of Garage Doors and Rolling Doors
4
NFRC 102-2002102 Procedure for Measuring the Steady-State Thermal Transmittance of Fenestration Systems
3. Terminology
3.1 Definitions—Definitions and terms are in accordance with Terminology E631 and C168, from which the following have
been selected and modified to apply specifically to fenestration systems. See Fig. 1 a
...