1、Designation: C687 12C687 17Standard Practice forDetermination of Thermal Resistance of Loose-Fill BuildingInsulation1This standard is issued under the fixed designation C687; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice presents a laboratory guide to determine the thermal resistance of loose-fill building insulations a
3、t meantemperatures between 20between 20 and 55C (4 to 131F).1.2 This practice applies to a wide variety of loose-fill thermal insulation products including fibrous glass, rock/slag wool, orcellulosic fiber materials; granular types including vermiculite and perlite; pelletized products; and any othe
4、r insulation materialinstalled pneumatically or poured in place. It does not apply to products that change their character after installation either bychemical reaction or the application of binders or adhesives, nor does it consider the effects of structures, containments, facings,or air films.1.3
5、Since this practice is designed for reproducible product comparison, it measures the thermal resistance of an insulationmaterial which has been preconditioned to a relatively dry state. Consideration of changes of thermal performance of a hygroscopicinsulation by sorption of water is beyond the scop
6、e of this practice.1.4 The sample preparation techniques outlined in this practice do not cover the characterization of loose-fill materials intendedfor enclosed applications. For those applications, a separate sample preparation technique that simulates the installed condition willbe required. Howe
7、ver, even for those applications, some other aspects of this practice are applicable.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.6 This standard does not purport to address all of the safety concerns, if any, associ
8、ated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on
9、 standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C167 Test Methods for Thickness and Densit
10、y of Blanket or Batt Thermal InsulationsC168 Terminology Relating to Thermal InsulationC177 Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of theGuarded-Hot-Plate ApparatusC518 Test Method for Steady-State Thermal Transmission Properties by Means of
11、the Heat Flow Meter ApparatusC653 Guide for Determination of the Thermal Resistance of Low-Density Blanket-Type Mineral Fiber InsulationC739 Specification for Cellulosic Fiber Loose-Fill Thermal InsulationC1045 Practice for Calculating Thermal Transmission Properties Under Steady-State ConditionsC11
12、14 Test Method for Steady-State Thermal Transmission Properties by Means of the Thin-Heater ApparatusC1363 Test Method for Thermal Performance of Building Materials and EnvelopeAssemblies by Means of a Hot BoxApparatusC1373 Practice for Determination of Thermal Resistance of Attic Insulation Systems
13、 Under Simulated Winter Conditions1 This practice is under the jurisdiction ofASTM Committee C16 on Thermal Insulation and is the direct responsibility of Subcommittee C16.30 on Thermal Measurement.Current edition approved Sept. 1, 2012March 15, 2017. Published October 2012April 2017. Originally app
14、roved in 1971. Last previous edition approved in 20072012 asC687 07.C687 12. DOI: 10.1520/C0687-12.10.1520/C0687-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to t
15、he standards Document Summary page on the ASTM website.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. Becauseit may not be technically possible to adequately depict all changes a
16、ccurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United
17、States13. Terminology3.1 Unless otherwise stated, the terms and definitions found in Terminology C168 are applicable herein.4. Significance and Use4.1 The thermal resistance, R, of an insulation is used to describe its thermal performance.4.2 The thermal resistance of an insulation is related to the
18、 density and thickness of the insulation. It is desirable to obtain testdata on thermal resistances at thicknesses and densities related to the end uses of the product.4.3 In normal use, the thickness of these products range from less than 100 mm (4 in.) to greater than 500 mm (20 in.). Installedden
19、sities depend upon the product type, the installed thickness, the installation equipment used, the installation techniques, and thegeometry of the insulated space.4.4 Loose-fill insulations provide coverage information using densities selected by manufacturers to represent the productsettled densiti
20、es. Generally, it is necessary to know the product thermal performance at a representative density. Some coveragecharts utilize multiple densities to show that greater thickness installations usually result in higher installed densities. The use ofmultiple densities can be detected from the coverage
21、 chart by calculating the density for several different thermal resistance levels.(The density for a given thermal resistance can be calculated from the coverage chart by dividing the minimum mass per unit areaby the minimum thickness.) If the calculated densities are significantly different at diff
22、erent thermal resistances, the multipledensity strategy has been used.4.5 When applicable specifications or codes do not specify the nominal thermal resistance level to be used for comparisonpurposes, a recommended practice is to use the Rsi (metric) = 3.3 m2K/W (RIP = 19 h ft2F/Btu) label density a
23、nd thickness forthat measurement.4.6 If the density for test purposes is not available from the coverage chart, a test density shall be established by use ofapplicable specifications and codes or, if none apply, agreement between the requesting body and the testing organization.4.7 Generally, thin s
24、ections of these materials are not uniform. Thus, the test thickness must be greater than or equal to theproducts representative thickness if the results are to be consistent and typical of use.NOTE 1The representative thickness is specific for each product and is determined by running a series of t
25、ests in which the density is held constantbut the thickness is increased. The representative thickness is defined here as that thickness above which there is no more than a 2 % change in theresistivity of the product. The representative thickness is a function of product blown density. In general, a
26、s the density decreases, the representativethickness increases. Fortunately, most products are designed to be blown over a small range of densities.This limited range yields a range of representativethicknesses between 100 to 200 mm (4 to 8 in.) for most products. To simplify the process for this Pr
27、actice, the representative thickness for the C687tests shall be determined at the midpoint of the blown density range. Once this is accomplished, all thermal testing on this product is conducted at athickness that is greater or equal to the representative thickness.4.7.1 For this practice, the minim
28、um test thickness shall be 100 mm (4 in.) or the representative thickness, whichever is larger.If the test is to represent an installation at a lesser thickness, the installed thickness shall be used.4.8 Because of the high cost of construction and operation of large test equipment, it is impractica
29、l to test at the higherthicknesses at which products are used. For purposes of this practice, it is acceptable to estimate the thermal resistance at anythickness from the thermal resistivity obtained from tests on the product at the minimum test thickness (see 4.7.1) and at the densityexpected for t
30、he proposed thickness.4.9 In principle, any of the standard methods for the determination of thermal resistance are suitable for loose-fill products.These include Test Methods C177, C518, C1114, and C1363. Of these test methods, the heat flow meter apparatus, Test MethodC518, is preferred because of
31、 its lower cost and shorter testing time.4.10 The thermal resistance of low-density insulations depend upon the direction of heat flow. Unless otherwise specified, testsshall be performed for the maximum heat flow condition, that is, a horizontal specimen with heat flow-up.4.11 Specimens shall be pr
32、epared in a manner consistent with the intended installation procedure. Products for pneumaticinstallation shall be pneumatically applied (blown), and products for pour-in-place installation shall be poured into specimenframes.4.12 Loosefill insulation installed in attic applications will have heat
33、flow up during the winter. At winter design conditions inmany areas, the winter design temperature difference will cause convective heat transfer to occur within some loose-fill insulations.The procedure outlined in Practice C687 is not applicable to that measurement unless a Test Method C1363 test
34、apparatus is usedto reproduce the correct boundary conditions. To determine how seasonal differences can affect product performance, use PracticeC1373. Practice C1373 measures the expected winter thermal performance of loose-fill insulation under simulated winter designtemperature conditions and pro
35、vides specimen requirements necessary for that determination.5. Apparatus5.1 Thermal test apparatus used for this practice shall meet these requirements.5.1.1 Conformance to StandardsThe apparatus shall conform to all requirements of the ASTM thermal test method used.C687 1725.1.2 Size and ErrorThe
36、apparatus shall be capable of testing specimens up to at least 150-mm (6-in.) thickness with anestimated error not greater than 1 % attributed to thickness/guard dimensions. (Parametric studies using a mathematical model ofthe proposed apparatus will give insight to this evaluation. For example see
37、Table 1 in the 1976 revision of Test Method C518.3)NOTE 2Thermal test apparatus in use for this practice have overall plate dimensions of 457 to 1220 mm (18 to 48 in.) square with metering areas152 to 457 mm (6 to 18 in.) square. Other sizes are acceptable if proper consideration of the size-thickne
38、ss restrictions as outlined in the test method areobserved in their design. (See Practice C1045 for additional discussion.)5.1.3 TemperatureAs a minimum, the apparatus shall be capable of testing at a mean temperature of 23.9C (75F) with atemperature difference of 20 to 28C (36 to 50F). The equipmen
39、t shall be calibrated at the same temperatures as the testconditions. Some existing test apparatus have been designed to provide measurements over a range of mean temperatures from 20to 55C (4 to 131F) and for a wider range of temperature differences.5.1.4 HumidityThe absolute humidity within the te
40、st apparatus shall be maintained low enough to prevent condensation withinthe specimen or on the cold plate(s).Amaximum 9C (48F) dew point is consistent with the recommended material conditioninglevels.5.1.5 Orientation and Direction of Heat FlowThe thermal test apparatus shall be capable of testing
41、 horizontal specimens withheat flow-up. This orientation represents the most adverse heat flow condition for testing between two solid boundaries.5.1.6 Thermal Test Specimen FrameThe test frame shall be sized to match the test apparatus and shall be made of materialshaving low thermal conductivity (
42、0.12 W/m K) and minimum thickness. A thin, thermally insignificant, screen or membrane isstretched across the bottom to support the material. Frames have fixed rigid sides or fold-down, collapsible, or compressible sides(see Fig. 1 and Fig. 2).5.2 Specimen Preparation Equipment:3 See Table 1, “Maxim
43、um Spacing Between Warm and Cold Plates of Heat Flowmeter Apparatus,” of Test Method C518 76 published in 1985 Annual Book of ASTMStandards, Vol 04.06.NOTE 1Dimensions to match thermal test apparatus.FIG. 1 Rigid Test FrameC687 1735.2.1 Blowing MachineA blowing apparatus is required when pneumatical
44、ly applied specimens are to be tested. Choose thecombination of hopper, blower, and hose size and length that is representative of common use for the application of the materialto be tested. The following machine specifications have been developed for use with mineral wool and cellulosic materials.5
45、.2.1.1 Mineral Fiber Insulations:(1) Blowing MachineA commercial blowing machine with a design capacity for delivering the subject material at a ratebetween 4 and 15 kg (9 to 33 lb)/min.(2) Blowing HoseThe machine shall utilize 46 m (150 ft) of typical 75 to 100 mm (3 to 4 in.) diameter flexible, in
46、ternallycorrugated blowing hose. At least 30 m (100 ft) of the hose shall be elevated between 3 and 6 m (10 and 20 ft) above the outletof the blowing machine to simulate a typical installation configuration. The hose shall have no more than eight 90 bends and allbends shall be greater than 1.2-m (4-
47、ft) radius. Before each sample preparation session, examine the hose for material remainingfrom previous blows. Dislodge any remaining material by mechanically agitating the hose when the machine is running. Repeatas necessary to maintain a clean hose for each specimen.(1) Blowing MachineA commercia
48、l blowing machine with a design capacity for delivering the subject material at a ratebetween 4 and 15 kg (9 to 33 lb)/min.(2) Blowing HoseThe machine shall utilize 46 m (150 ft) of typical 75 to 100 mm (3 to 4 in.) diameter flexible, internallycorrugated blowing hose. At least 30 m (100 ft) of the
49、hose shall be elevated between 3 and 6 m (10 and 20 ft) above the blowingmachine to simulate a typical installation configuration. The hose shall have no more than eight 90 bends and all bends shall begreater than 1.2-m (4-ft) radius. Before each sample preparation session, examine the hose for material remaining from previousblows. Dislodge any remaining material by mechanically agitating the hose when the machine is running. Repeat as necessary tomaintain a clean hose for each specimen.NOTE 3In case of dispute, for mineral fiber insulati
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