1、Designation: D 4897 01Standard Specification forAsphalt-Coated Glass-Fiber Venting Base Sheet Used inRoofing1This standard is issued under the fixed designation D 4897; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers asphalt-impr
3、egnated andcoated glass-fiber base sheet with mineral surfacing on the topside and coarse mineral granules on the bottom side for use asthe first ply of a roofing membrane. These base sheets providefor the lateral release of pressure in roofing systems becausethey are not solidly attached and the co
4、arse granular surfaceprovides an open, porous channel in the horizontal planebeneath the membrane. The base sheets shall be permitted to bewith or without perforations or embossings.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informati
5、ononly.2. Referenced Documents2.1 ASTM Standards:D 146 Test Methods for Sampling and Testing Bitumen-Saturated Felts and Woven Fabrics for Roofing and Wa-terproofing2D 228 Test Methods for Sampling, Testing, and Analysis ofAsphalt Roll Roofing, Cap Sheets, and Shingles Used inRoofing and Waterproofi
6、ng2D 1079 Terminology Relating to Roofing, Waterproofing,and Bituminous Materials23. Terminology3.1 DefinitionsFor definitions of terms used in this speci-fication, refer to Terminology D 1079.4. Classification4.1 Type IIHeavy-duty asphalt-coated glass-fiber ventingbase sheet.5. Materials and Manufa
7、cture5.1 The mat shall be a thin porous sheet of uniformlydistributed glass fibers, with or without the addition of rein-forcing strands, or glass yarns, which are bonded with awater-resistant resinous binder.5.2 In the process of manufacture, the glass mat is impreg-nated and coated on both sides w
8、ith a hot asphaltic coating withor without a mineral stabilizer and surfaced on the bottom sidewith coarse mineral granules embedded in an asphaltic coating.The top side shall be surfaced with fine mineral surfacing.5.3 The product shall be permitted to be embossed orunembossed on the bottom side. T
9、he product shall be permittedto contain holes designated for attachment with moppingasphalt.6. Physical Requirements, Dimensions, and Masses6.1 The material at the point of manufacture shall conformto the physical requirements in Table 1 and the dimensions andmasses in Table 2.6.2 The finished produ
10、ct shall not crack nor be so sticky asto cause tearing or other damage upon being unrolled attemperatures between 10 and 60C (50 and 140F).6.3 Pliability at 25 6 1C (77 6 2F)At least eight out often strips shall not crack when tested in accordance with TestMethods D 228 except, for convenience, that
11、 the strips shall beconditioned in ambient conditions at 25 6 1C (77 6 2F) forat least 30 min before testing over a 19-mm (34-in.) radius.6.4 Loss and Behavior on HeatingThere shall be noflowing, sagging, or blistering of the asphalt coating whentested in accordance with Test Methods D 228.1This spe
12、cification is under the jurisdicton of ASTM Committee D08 onRoofing, Waterproofing, and Bituminous Materials and is the direct responsibility ofSubcommittee D08.04 on Felts and Fabrics for Bituminous Roofing and Water-proofing.Current edition approved November 10, 2001. Published March 2002. Origina
13、llypublished as D 4897 89. Last previous edition D 4897 98.2Annual Book of ASTM Standards, Vol 04.04.TABLE 1 Physical RequirementsType IIBreaking strength, min, at 25 6 1C (77 6 2F)kN/m (lbf/in.)longitudinal and transverse7.7 (44)Diameter of spot-mopping holes, (when present)max, mm (in.)25 (1.0)Spa
14、cing of holes, center-to-center (when present)min, mm (in.)51 (2.0)max, mm (in.) 152 (6.0)1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Workmanship, Finish, and Appearance7.1 The glass mat shall be impregnated and shall show now
15、hite spots at any point.7.2 The coating shall be applied to each side to the edges ofthe sheet. The coating must be smooth.7.3 The top side shall be surfaced with mineral surfacing toprevent the roofing from sticking in the package.7.4 The bottom side shall be surfaced with coarse mineralmatter, at
16、least 90 % retained on a 212-m (No. 70) sieve,embedded in the asphalt coating.7.5 The finished material shall be free of visible externaldefects, such as holes, ragged or untrue edges, breaks, cracks,tears, protuberances, and indentations, except for intentionallyprovided holes or embossing.7.6 Embo
17、ssing, when present, should be of such a characterthat it does not cause the product to be susceptible to handlingdamage.8. Sampling and Test Methods8.1 Sample the material and determine the properties enu-merated in this specification in accordance with Test MethodsD 146 and D 228.9. Inspection9.1
18、InspectionInspection shall be in accordance with therequirements of this specification.9.2 Inspection AlternativesAlternative inspection require-ments shall be determined by and as agreed upon between thepurchaser and the supplier.10. Rejection and Resubmittal10.1 Failure to ConformFailure to confor
19、m to any of therequirements as stated in this specification constitutes groundsfor rejection.10.2 Rejection RedressThe supplier shall have the right toinspect the rejected materials. The supplier and the purchasershall agree to the quantity of rolls deemed unacceptable. Thesupplier shall then have t
20、he right to submit the same number ofnew rolls as replacement.11. Packaging and Marking11.1 Unless otherwise agreed upon between the supplier andpurchaser, each product package shall be plainly marked withthe suppliers name, the product brand, the ASTM designation,and type of bitumen if not evident
21、in the label name of theproduct.11.2 The rolls shall be securely wrapped or banded in amanner that completely encircles the roll and will preventslipping or unrolling.11.3 No roll shall contain more than two pieces, and nomore than 3 % of the rolls in any lot shall contain two pieces.If a roll conta
22、ins a manufacturing splice, the splice shall beclearly marked.12. Keywords12.1 base sheet; first ply; glass fiber; impregnated andcoated; partially attachedASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard
23、. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed
24、every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible te
25、chnical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshoh
26、ocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 2 Dimensions and Ma
27、ssesAType IIWidth of roll, mm (in.) 36 (914) 6 0.7 %Area of roll, min, m2(ft2) 9.64 (104)Mass of any roofing in shipment min, g/m2(lb/100 ft2) 2685 (55)Mass of desaturated glass mat min, g/m2(lb/100 ft2) 83 (1.7)Mass of asphalt, min, gm/m2(lb/100 ft2) 586 (12)Mass of total unstabilized coating, fill
28、er and top surfacing min, g/m2(lb/100 ft2) 1075 (22.0)Mass of mineral granules retained on a 212-m (No. 70) sieve min, g/m2(lb/100 ft2) 391 (8.0)Mass of mineral matter passing a 212-m (No. 70) sieve on basis of total mass of mineral stabilized coatingand top surface mineral matter, max, %60Ash (glass mat only), % 7088Moisture at point of manufacture, max, % 1.0ATypes cannot be differentiated after installation and must be tested for compliance to the specification before application.D4897012
