1、Designation: C 1373 03Standard Practice forDetermination of Thermal Resistance of Attic InsulationSystems Under Simulated Winter Conditions1This standard is issued under the fixed designation C 1373; the number immediately following the designation indicates the year oforiginal adoption or, in the c
2、ase of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice presents a laboratory procedure to deter-mine the thermal resistance of at
3、tic insulation systems undersimulated steady-state winter conditions. The practice appliesonly to attic insulation systems that face an open attic air space.1.2 The thermal resistance of the insulation is inferred fromcalculations based on measurements on a ceiling systemconsisting of components con
4、sistent with the system beingstudied. For example, such a system might consist of a gypsumboard or plywood ceiling, wood ceiling joists, and atticinsulation with its top exposed to an open air space. Thetemperature applied to the gypsum board or plywood shall bein the range of 18 to 24C (64 to 75F).
5、 The air temperatureabove the insulation shall correspond to winter conditions andmay range from 46C to 10C (51 to 50F). The gypsumboard or plywood ceiling shall be sealed to prevent directairflow between the warm and cold sides of the system.1.3 This practice applies to a wide variety of loose-fill
6、 orblanket thermal insulation products including fibrous glass,rock/slag wool, or cellulosic fiber materials; granular typesincluding vermiculite and perlite; pelletized products; and anyother insulation material that may be installed pneumatically orpoured in place. The practice considers the effec
7、ts on heattransfer of structures, specifically the ceiling joists, substrate,for example, gypsum board, air films, and possible facings,films, or other materials that may be used in conjunction withthe insulation.1.4 This practice measures the thermal resistance of theattic/ceiling system in which t
8、he insulation material has beenpreconditioned according to the material Specifications C 549,C 665, C 739, and C 764.1.5 The specimen preparation techniques outlined in thisstandard do not cover the characterization of loose-fill materi-als intended for enclosed applications.1.6 This practice may be
9、 used to characterize materialbehavior under controlled steady-state laboratory conditionsintended to simulate actual temperature conditions of use. Thepractice does not simulate forced air flow conditions.1.7 All values shall be reported in both SI and inch-poundunits unless specified otherwise by
10、the client.1.8 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. R
11、eferenced Documents2.1 ASTM Standards:C 167 Test Methods for Thickness and Density of Blanketor Batt Thermal Insulations2C 168 Terminology Relating to Thermal Insulation2C 177 Test Method for Steady-State Heat Flux Measure-ments and Thermal Transmission Properties by Means ofthe Guarded Hot Plate Ap
12、paratus2C 518 Test Method for Steady-State Thermal TransmissionProperties by Means of the Heat Flow Meter Apparatus2C 520 Test Methods for Density of Granular Loose-FillInsulations2C 549 Specification for Perlite Loose Fill Insulation2C 665 Specification for Mineral-Fiber Blanket Thermal In-sulation
13、 for Light Frame Construction and ManufacturedHousing2C 687 Practice for Determination of Thermal Resistance ofLoose-Fill Building Insulation2C 739 Specification for Cellulosic Fiber (Wood Base)Loose-Fill Thermal Insulation2C 764 Specification for Mineral Fiber Loose-Fill ThermalInsulation2C 1045 Pr
14、actice for Calculating Thermal TransmissionProperties from Steady-State Conditions2C 1058 Practice for Selecting Temperatures for Evaluatingand Reporting Thermal Properties of Thermal Insulation21This practice is under the jurisdiction of ASTM Committee C16 on ThermalInsulation and is the direct res
15、ponsibility of Subcommittee C16.30 on ThermalMeasurements.Current edition approved April 10, 2003. Published May 2003.Orginally ap-proved in 1998. Last previous edition approved in 2001 as C 137301.2Annual Book of ASTM Standards, Vol 04.06.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box
16、 C700, West Conshohocken, PA 19428-2959, United States.C 1114 Test Method for Steady-State Thermal TransmissionProperties by Means of the Thin-Heater Apparatus2C 1363 Test Method for the Thermal Performance of Build-ing Assemblies by Means of a Hot Box Apparatus23. Terminology3.1 Definitions Unless
17、otherwise stated, the definitionslisted in Terminology C 168 are applicable herein.4. Significance and Use4.1 The thermal resistance of a ceiling system is used tocharacterize its steady-state thermal performance.4.2 The thermal resistance of insulation is related to thedensity and thickness of the
18、insulation. Test data on thermalresistance are obtained at a thickness and density representativeof the end use applications. In addition, the thermal resistanceof the insulation system will be different from that of thethermal insulation alone because of the system constructionand materials.4.3 Thi
19、s practice is needed because the in-service thermalresistance of some permeable attic insulations under winterconditions may be different, lower or higher R, than thatmeasured at or close to simulated room temperature conditionsutilizing small-scale tests in which the insulation is sandwichedbetween
20、 two isothermal impermeable plates that have a tem-perature difference (DT) of 20 to 30C (36 to 54F). When suchinsulation is installed in an attic, on top of a ceiling composedof normal building materials such as gypsum board or ply-wood, with an open top surface exposed to the attic air space,the t
21、hermal resistance under winter conditions with heat flowup and large temperature differences may be significantly lessbecause of additional heat transfer by natural convection. Fig.1 illustrates the difference between results from small scaletests and tests under the conditions of this practice. See
22、 Ref(1-12) for discussions of this phenomenon.34.4 In normal use, the thickness of insulation products mayrange from 75 mm (3 in.) to 500 mm (20 in.). Installeddensities will depend upon the product type, the installedthickness, the installation equipment used, the installationtechnique, and the geo
23、metry of the insulated space.4.5 The onset of natural convection under winter conditionsmay be a function of specimen thickness. For purposes of thispractice, the tests shall be carried out at thicknesses at whichthe product is used.4.6 Since this practice simulates winter conditions, the heatflow d
24、irection shall be vertically upwards.4.7 Specimens shall be prepared in a manner consistent withthe intended installation procedure. Products for pneumaticinstallation shall be pneumatically-applied (blown), and prod-ucts for pour-in-place installation shall be poured into place.See 5.2.5. Equipment
25、5.1 Thermal test apparatus used for this practice shall meetthe following requirements:5.1.1 Conformance to StandardsThe apparatus shall con-form to all requirements of the ASTM thermal test methodused, except as required by 5.1.2-5.1.6.5.1.2 SizeThe apparatus shall be capable of testing speci-mens
26、at the thickness intended for product use. Length andwidth of the metering area shall be at least twice the spacing ofthe wood joists or four times the specimen thickness, which-ever is greater (see Fig. 2).5.1.3 Temperature The apparatus shall be capable oftesting with the hot side surface maintain
27、ed between 18 and24C (64 and 75F), and with the cold side air temperaturemaintained near the winter condition for the particular climatebeing simulated, which may range from 46 to 10C (51 to50F). In the absence of specified temperatures, the ambient3The boldface numbers in parentheses refer to the l
28、ist of references at the end ofthis standard.NOTE 1A constant hot-side temperature (T, hot) is used for both testsand 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
29、Permeable AtticInsulation Under Simulated Winter Conditions (Heat Flow Up)FIG. 2 Requirements on Dimensions of Test Specimen MeteringAreaC1373032temperatures listed in Table 2 of C 1058 on Temperatures forThermal Transmittance Evaluations may be used.NOTE 1Only those with a hot ambient of 24C (75F)
30、are applicable.5.1.4 HumidityThe absolute humidity on both sides of thetest apparatus shall be maintained low enough to preventcondensation within the specimen. See 6.9.6 of Test MethodC 1363 for humidity requirements for the hot box methods, 6.6of Test Method C 177 for the guarded hot plate method,
31、 and7.10 of Test Method C 518 for the heat flow meter apparatus.5.1.5 Orientation and Direction of Heat FlowThe thermaltest specimen shall be oriented horizontally with heat flow up.5.1.6 Thermal Test Specimen and HolderThe test assem-bly shall be sized to match the test apparatus and shall be madeo
32、f construction materials representative of the intended appli-cation. The substrate on which the insulation rests shall berepresentative of the intended application, typically gypsumboard. The substrate shall be sealed to prevent direct airflowbetween the warm and cold sides of the system. Wood jois
33、tsalso shall be included. The test assembly shall be constructedsuch that the top of the insulation is open to an air space havinga minimum thickness of 150 mm (6 in.). Test Methods C 1363is preferred because of its ability to accommodate a large airspace. Other apparatuses that can simulate in-serv
34、ice condi-tions also may be used, (for example, modifications of TestMethods C 177, C 518,orC 1114 with Practice C 1045). In allcases, the size requirements given in 5.1.2 shall be met. Fig. 3shows a schematic of an attic test module that has been used forthese types of tests. Other configurations w
35、ithout the roofstructure are acceptable as long as the minimum 150 mm (6 in.)air space is maintained.5.2 Specimen Preparation Equipment:5.2.1 Blowing ApparatusA blowing apparatus is requiredwhen pneumatically-applied specimens are to be tested.Choose the combination of hopper, blower, hose size andl
36、ength that is representative of common use for the applicationof the material to be tested. The following machine specifica-tions have been developed for use with mineral fiber andcellulosic materials.5.2.1.1 A commercial blowing machine with a design ca-pacity for delivering the subject material at
37、 a rate recom-mended by the insulation manufacturer shall be used. Themachine should utilize 46 m (150 ft) of flexible, internallycorrugated blowing hose with an appropriate sized diameter asspecified by the machine manufacturer. At least 30 m (100 ft)of the hose should be elevated between 3 and 6 m
38、 (10 and 20ft) above the blowing machine to simulate typical installationFIG. 3 Schematic of Attic Test Module and Large Scale Climate Simulator Used for Tests on Attic Insulation Under Simulated WinterConditionsC1373033configuration. The hose should have no more than eight 90bends and no bends may
39、be less than 1.2 m (4 ft) radius. It isgood practice to clean the hose periodically by mechanicallyagitating it with the blower operating. This practice shoulddislodge any pieces of old insulation that might be caught inthe hose.6. Sampling6.1 A sample of material shall be selected from a lotaccordi
40、ng to sampling plans given in the material specifica-tions, regulations, or other appropriate documents when appli-cable. In the absence of such directions, material from at leasttwo randomly chosen packages shall be combined in equalportions (mass) so as to combine materials as uniformly aspractica
41、ble.6.2 The insulation material should be preconditioned to amoisture content in equilibrium with the laboratory conditionsprior to the specimen installation. Preconditioning of materialsnot only ensures controlled installation conditions but mayreduce the time required to condition the prepared spe
42、cimenprior to thermal testing. For conditioning requirements, see theapplicable materials Specifications C 520, C 549, C 665,C 739, and C 764.7. Specimen Preparation7.1 General Instructions:7.1.1 All specimens shall be prepared to a thickness and unitarea mass that are given for the label R-value sp
43、ecification ofinterest for the material under test.7.1.2 Specimens shall be prepared in a manner consistentwith the intended installation procedure. All materials shall beinstalled carefully using the manufacturers recommendedinstallation practice. Batts shall be cut, as required, to fit theavailabl
44、e specimen holder. Products for pneumatic installationshall be pneumatically-applied (blown), and products forpour-in-place installation shall be poured into the specimenholder. See 7.2.2 for the density of pneumatically-installedinsulation. Other materials should be installed at the densitysuggeste
45、d by the manufacturer.7.1.3 The specimen holder shall represent typical atticframe construction, wherever possible. This requires, as aminimum, horizontal members representing the bottom chordof a truss system or rafter framing and an air-tight gypsumboard or plywood bottom. The specimen holder shal
46、l be cleanand free of insulation residue prior to installation of the sampleinsulation.NOTE 2For commonly available loose-fill insulation, state and federalenergy codes, ASTM material specifications and the Federal TradeCommission have identified those materials that shall apply a correctionfor sett
47、ling when determining thermal performance. It is beyond the scopeof this practice to outline the procedures for this determination.NOTE 3Many factors can influence the characteristics of the loose-fillinsulation. These include blowing rate, machine adjustments, the size andlength of the hose, and th
48、e angle and dimensions of the hose outlet inrelation to the specimen holder. Trained operators are required to duplicatefield-installed conditioning.NOTE 4For these tests, the specimen shall be blown close to thelabeled density. Some operators may wish to establish a target mass ofinsulation require
49、d to fill the test frame to the desired thickness anddensity as a control during the specimen preparation process. By weighingthe initial material and that remaining after blowing is complete, theoperator can estimate the material in the test frame. Other operators maywish to eliminate these extra steps. The reported test density, however, isobtained from the metering area density measurement conducted after thethermal test.7.2 Specimen PreparationPneumatic-Application:7.2.1 The procedure described in this section is intended forall products, which norma
