ASTM C991-23

Standard Specification for Flexible Fibrous Glass Insulation for Metal Buildings

ABSTRACT
This specification covers the classification, composition, and physical properties of flexible fibrous glass insulation for use as interior surface of walls and roofs of metal buildings. The basic insulation blanket is designed to be postprocessed by a laminating process that applies an adhesive bonded facing to provide the interior finish and vapor retarder requirements for the building envelope The flexible insulation is furnished into Types I and II. Type I which is a glass processed from the molten state into fibrous form, bonded with a thermosetting resin, and formed into a resilient flexible blanket or batt. Type II is a Type I material supplied with a suitable facing adhered to one surface. The following physical properties of Types I and II materials shall be determined: thermal resistance, surface burning characteristics, combustion characteristics, water vapor sorption, fungi resistance, corrosiveness, odor emission, dimensional tolerances, and humid aging.
SCOPE
1.1 This specification covers the classification, composition, and physical properties of flexible fibrous glass insulation for use in metal building roofs and walls.  
1.2 The basic insulation blanket is designed to be post-processed by a laminating process that applies an adhesive bonded facing.  
1.3 The thermal values measured in accordance with this specification for both pre-processed and post-processed insulation are for the insulation only and do not include the effects of air-film surface resistance, changes in mean temperature, or compression of insulation at the framing members of the building, through metal conductance of fasteners and other parallel heat-transfer paths due to design or installation techniques.  
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that 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: 30-Apr-2023
• ICS: 91.100.60 - Thermal and sound insulating materials
• Technical Committee: C16 - Thermal Insulation
• Drafting Committee: C16.23 - Blanket and Loose Fill Insulation

Relations

• Refers: ASTM C755-20 - Standard Practice for Selection of Water Vapor Retarders for Thermal Insulation
• Effective Date: 01-Mar-2020

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: C991 − 23
Standard Specification for
1
Flexible Fibrous Glass Insulation for Metal Buildings
This standard is issued under the fixed designation C991; 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 C167 Test Methods for Thickness and Density of Blanket or
Batt Thermal Insulations
1.1 This specification covers the classification, composition,
C168 Terminology Relating to Thermal Insulation
and physical properties of flexible fibrous glass insulation for
C177 Test Method for Steady-State Heat Flux Measure-
use in metal building roofs and walls.
ments and Thermal Transmission Properties by Means of
1.2 The basic insulation blanket is designed to be post-
the Guarded-Hot-Plate Apparatus
processed by a laminating process that applies an adhesive
C390 Practice for Sampling and Acceptance of Thermal
bonded facing.
Insulation Lots
1.3 The thermal values measured in accordance with this C518 Test Method for Steady-State Thermal Transmission
Properties by Means of the Heat Flow Meter Apparatus
specification for both pre-processed and post-processed insu-
lation are for the insulation only and do not include the effects C653 Guide for Determination of the Thermal Resistance of
Low-Density Blanket-Type Mineral Fiber Insulation
of air-film surface resistance, changes in mean temperature, or
compression of insulation at the framing members of the C665 Specification for Mineral-Fiber Blanket Thermal Insu-
lation for Light Frame Construction and Manufactured
building, through metal conductance of fasteners and other
parallel heat-transfer paths due to design or installation tech- Housing
C755 Practice for Selection of Water Vapor Retarders for
niques.
Thermal Insulation
1.4 The values stated in inch-pound units are to be regarded
C1045 Practice for Calculating Thermal Transmission Prop-
as standard. The values given in parentheses are mathematical
erties Under Steady-State Conditions
conversions to SI units that are provided for information only
C1104/C1104M Test Method for Determining the Water
and are not considered standard.
Vapor Sorption of Unfaced Mineral Fiber Insulation
1.5 This standard does not purport to address all of the
C1136 Specification for Flexible, Low Permeance Vapor
safety concerns, if any, associated with its use. It is the
Retarders for Thermal Insulation
responsibility of the user of this standard to establish appro-
C1304 Test Method for Assessing the Odor Emission of
priate safety, health, and environmental practices and deter-
Thermal Insulation Materials
mine the applicability of regulatory limitations prior to use.
C1338 Test Method for Determining Fungi Resistance of
1.6 This international standard was developed in accor-
Insulation Materials and Facings
dance with internationally recognized principles on standard-
C1617 Practice for Quantitative Accelerated Laboratory
ization established in the Decision on Principles for the
Evaluation of Extraction Solutions Containing Ions
Development of International Standards, Guides and Recom-
Leached from Thermal Insulation on Aqueous Corrosion
mendations issued by the World Trade Organization Technical
of Metals
Barriers to Trade (TBT) Committee.
E84 Test Method for Surface Burning Characteristics of
Building Materials
2. Referenced Documents
E136 Test Method for Assessing Combustibility of Materials
2
2.1 ASTM Standards:
Using a Vertical Tube Furnace at 750 °C
E2988 Practice for Specimen Preparation and Mounting of
Flexible Fibrous Glass Insulation for Metal Buildings to
1
This specification is under the jurisdiction of ASTM Committee C16 on
Thermal Insulation and is the direct responsibility of Subcommittee C16.23 on Assess Surface Burning Characteristics
Blanket and Loose Fill Insulation.
2.2 Other Referenced Document:
Current edition approved May 1, 2023. Published May 2023. Originally
CAN/ULC-S102 Standard Method of Test for Surface Burn-
approved in 1983. Last previous edition approved in 2016 as C991 – 16. DOI:
3
ing Characteristics of Building Materials and Assemblies
10.1520/C0991-23.
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
3
Standards volume information, refer to the standard’s Document Summary page on Available from Underwriters Laboratories (UL), 333 Pfingsten Rd.,
the ASTM website. Northbrook, IL 60062-2096, http://www.ul.com.
Copyright © ASTM International,
...

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: C991 − 16 C991 − 23
Standard Specification for
1
Flexible Fibrous Glass Insulation for Metal Buildings
This standard is issued under the fixed designation C991; 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 specification covers the classification, composition, and physical properties of flexible fibrous glass insulation for use in
metal building roofs and walls.
1.2 The basic insulation blanket is designed to be post-processed by a laminating process that applies an adhesive bonded facing.
1.3 The thermal values measured in accordance with this specification for both pre-processed and post-processed insulation are
for the insulation only and do not include the effects of air-film surface resistance, changes in mean temperature, or compression
of insulation at the framing members of the building, through metal conductance of fasteners and other parallel heat-transfer paths
due to design or installation techniques.
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that 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 and healthsafety, health, and environmental practices and determine
the applicability of regulatory requirementslimitations 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:
C167 Test Methods for Thickness and Density of Blanket or Batt Thermal Insulations
C168 Terminology Relating to Thermal Insulation
C177 Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the
Guarded-Hot-Plate Apparatus
C390 Practice for Sampling and Acceptance of Thermal Insulation Lots
C518 Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus
C653 Guide for Determination of the Thermal Resistance of Low-Density Blanket-Type Mineral Fiber Insulation
C665 Specification for Mineral-Fiber Blanket Thermal Insulation for Light Frame Construction and Manufactured Housing
1
This specification is under the jurisdiction of ASTM Committee C16 on Thermal Insulation and is the direct responsibility of Subcommittee C16.23 on Blanket and Loose
Fill Insulation.
Current edition approved May 1, 2016May 1, 2023. Published June 2016May 2023. Originally approved in 1983. Last previous edition approved in 20152016 as
C991 – 15.C991 – 16. DOI: 10.1520/C0991-16.10.1520/C0991-23.
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’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

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C991 − 23
C755 Practice for Selection of Water Vapor Retarders for Thermal Insulation
C1045 Practice for Calculating Thermal Transmission Properties Under Steady-State Conditions
C1104/C1104M Test Method for Determining the Water Vapor Sorption of Unfaced Mineral Fiber Insulation
C1136 Specification for Flexible, Low Permeance Vapor Retarders for Thermal Insulation
C1304 Test Method for Assessing the Odor Emission of Thermal Insulation Materials
C1338 Test Method for Determining Fungi Resistance of Insulation Materials and Facings
C1617 Practice for Quantitative Accelerated Laboratory Evaluation of Extraction Solutions Containing Ions Leached from
Thermal Insulation on Aqueous Corrosion of Metals
E84 Test Method for Surface Burning Characteristics of Building Materials
E136 Test Method for Assessing Combustibility of Materials Using a Vertical Tube Furnace at 750 °C
E2988 Practice for Specimen Preparation and Mounting of Flexible
...