1、Designation: E 1646 95 (Reapproved 2003)Standard Test Method forWater Penetration of Exterior Metal Roof Panel Systems byUniform Static Air Pressure Difference1This standard is issued under the fixed designation E 1646; the number immediately following the designation indicates the year oforiginal a
2、doption or, in the case 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 test method covers the determination of the resis-tance of exte
3、rior metal roof panel systems to water penetrationwhen water is applied to the outdoor face simultaneously witha static air pressure at the outdoor face higher than the pressureat the indoor face, that is, positive pressure. This test method isa specialized adaption of Test Method E 331.1.2 This tes
4、t method is applicable to any roof area and isintended to measure only the water penetration associated withthe field of roof including panel side laps and structuralconnections. It does not include leakage at openings orperimeter or any other details.1.3 This test method is limited to specimens in
5、which theside seams and attachments are clearly visible and in which thesource of leakage is readily determined. Composite systems inwhich the source cannot be readily determined are outside thescope of this test method.1.4 The proper use of this test method requires a knowledgeof the principles of
6、pressure and flow measurement.1.5 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only and may be approximate.1.6 The text of this test method references notes andfootnotes excluding tables and figures, which provide explana
7、-tory material. These notes and footnotes shall not be consid-ered as requirements of the test method.1.7 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 he
8、alth practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardstatements, see 7.1.2. Referenced Documents2.1 ASTM Standards:E 331 Test Method for Water Penetration of Exterior Win-dows, Skylights, Doors, and Curtain Walls by UniformStatic Air Pressure Dif
9、ference2E 631 Terminology of Building Construction2E 1680 Test Method for Rate of Air Leakage ThroughExterior Metal Roof Panel Systems3E 1592 Test Method for Structural Performance of SheetMetal Roof and Siding Systems by Uniform Static AirPressure Difference22.2 Other Standard:AAMA 501 Methods of T
10、est for Metal Curtain Walls43. Terminology3.1 DefinitionsFor definitions of general terms relating tobuilding construction used in this test method, see TerminologyE 631.3.2 Descriptions of Terms Specific to This Standard:3.2.1 specimenthe entire assembled unit submitted fortest as described in Sect
11、ion 8.3.2.2 test pressure differencethe specified difference instatic air pressure across the assembled and fixed specimenexpressed as pounds-force per square foot (newtons per squaremetre (pascals).3.2.3 water leakagepenetration of water onto the exposedinside surface of the test specimen under spe
12、cified conditionsof air pressure difference across the specimen during a 15-mintest period. Water penetration at or around end dams or siderails is not leakage; end dams and side rails are installed tocause and control ponding over the panels and to support thepanels. They are not part of the roof.4
13、. Summary of Test Method4.1 This test method consists of sealing and fixing the testspecimen into or against one face of a test chamber, supplyingair to or exhausting air from the chamber at the rate required tomaintain the test pressure difference across the specimen, while1This test method is unde
14、r the jurisdiction of ASTM Committee E06 onPerformance of Buildings and is the direct responsibility of Subcommittee E06.57on Performance of Metal Roof Systems.Current edition approved April 10, 2003. Published May 2003. Originallyapproved in 1995. Last previous edition approved in 1995 as E 1646 95
15、.2Annual Book of ASTM Standards, Vol 04.11.3Annual Book of ASTM Standards, Vol 04.12.4Available from Architectural Aluminum Manufacturers Association (AAMA),1827 Walden Office Square, Suite 550, Schaumburg, IL 60173.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken
16、, PA 19428-2959, United States.spraying water onto the outdoor face of the specimen at therequired rate and observing any water leakage.5. Significance and Use5.1 This test method is a standard procedure for determiningthe resistance to water penetration under uniform positive staticair pressure dif
17、ferences, and simulates wind driven rain im-posed on sidelaps and rain that is free to drain while buildinga water head as it flows. The slope of the roof is significant.These factors shall be fully considered prior to specifying thetest pressure difference.NOTE 1In applying the results of tests by
18、this method, note that theperformance of a roof or its components, or both, may be a function ofproper installation and adjustment. In service, the performance alsodepends on the rigidity of supporting construction, roof slope, and on theresistance of components to deterioration by various causes: c
19、orrosiveatmosphere, aging, ice, vibration, thermal expansion and contraction, etc.It is difficult to simulate the identical complex wetting conditions that canbe encountered in service, including large wind-blown water drops,increasing water drop impact pressures with increasing wind velocity, andla
20、teral or upward moving air and water. Some designs are more sensitivethan others to this upward moving water.NOTE 2This is a test procedure. It is the responsibility of thespecifying agency to determine the specimen construction, size, and testpressures after considering the methods guidelines. Prac
21、tical consider-ations suggest that every combination of panel thickness, span, and designload need not be tested in order to substantiate product performance.NOTE 3This test method shall not, by itself, be relied upon to formconclusions about overall water penetration through metal roofs. A roofcont
22、ains many details. Although prescribed modifications are outside thescope of this test method, an experienced testing engineer is able to use theprinciples presented in this test method and generate significant data byisolating specific details and measuring leakage.6. Apparatus6.1 The description o
23、f apparatus in this section is general innature, and any arrangement of equipment capable of perform-ing the test procedure within the allowable tolerances ispermitted.6.2 Major Components (see Fig. 1):6.2.1 Test ChamberA test chamber or box with either anopening, a removable mounting panel, or one
24、open face inwhich or against which the specimen is installed and sealed.The specimen shall be installed horizontally. Chamber designshall not allow run-off from the test chamber to drain onto thetest specimen. At least one static pressure tap shall be providedto measure the chamber pressure and shal
25、l be so located thatthe reading is unaffected by the velocity of the air supply to orfrom the chamber. The air supply opening into the chambershall be arranged so that the air does not impinge directly onthe test specimen with any significant velocity. When required,a means of access shall be provid
26、ed into the chamber tofacilitate adjustments and observations after the specimen hasbeen installed.NOTE 4Uniform ponding is essential to this test methodrefer to 5.1.For this reason the specimen slope must be horizontal, and the overflowdevices described in 8.3 are required to control ponding. Chamb
27、er run-offthat drains onto the specimen is not allowed so that the accuracy anduniformity of the metered flow rate described in 6.2.4 is not compromised.6.2.2 Air SystemA controllable blower, compressed airsupply, exhaust system, or reversible blower designed toprovide the required maximum air-press
28、ure difference acrossthe specimen. The system must provide essentially constantairflow at a fixed pressure for the required test period and becapable of maintaining positive and negative pressures.6.2.3 Pressure-Measuring ApparatusA device to measurethe test pressure difference within a tolerance of
29、 62 %. Thedevice must measure positive and negative pressures.6.2.4 Water-Spray SystemThe water-spray system shalldeliver water uniformly against the exterior surface of the testspecimen at a minimum rate of 5.0 U.S. gal/ft2per h or 8 in./h(3.4 L/m2per min).6.2.4.1 The water-spray system shall have
30、nozzles spacedon a uniform grid, located at a uniform distance approximately12 in. (0.3 m) above the test specimen, and be adjustable toprovide the specified quantity of water in such a manner as towet the test specimen uniformly and to wet those areasvulnerable to water leakage. The spray must be d
31、irected at alloverlapping side seams with the stream centerline approxi-mately 20 off vertical (see Fig. 1). If additional nozzles arerequired to provide uniformity of water spray at the edge of thetest specimen, they shall be equally spaced around the entirespray grid.7. Hazards7.1 WarningGlass bre
32、akage and specimen failure do notnormally occur at the small pressure differences applied in thistest. Larger or excessive pressure differences occur duringpreload or due to error in operation or when the apparatus isused for other purposes such as structural testing; therefore,exercise adequate pre
33、cautions to protect personnel.8. Test Specimen8.1 Roof test specimens shall be of sufficient size todetermine the performance of all typical parts of the roofsystem. For roofs constructed with prefabricated or preformedunits or panels, the specimen width shall be equivalent to orgreater than the wid
34、th of three typical units plus the side railsupporting elements at each edge. The specimen shall containat least three assembled side lap seams; this allows partialwidth units. The specimen width shall be sufficient to provideloading on at least one typical unit (see Fig. 1). The specimenshall be of
35、 sufficient length to develop a multispan conditionunless the panel is used only in single span applications. If twospans are used, they shall be unequal, with the shorter being75 % of the longer. One panel end lap is optional but shall notbe used if the test will be run in tandem with Test MethodE
36、1680. However, one end lap is allowed if the specifyingauthority adopts the option at Test Method E 1680.NOTE 5The unbalanced span criterion more closely simulates multi-span panel deflection curvature. This works the panel sidelap whileminimizing specimen length.8.1.1 All parts of the roof test spe
37、cimen shall be full size,using the same materials, details, and methods of constructionand anchorage as used on actual buildings.8.1.2 Condition of structural support shall be simulated asaccurately as possible. If the roof system accommodatesthermal expansion parallel to the panel, this detail must
38、 beE 1646 95 (2003)2FIG. 1 General Arrangement of Water Leakage Apparatus Positive Chamber SystemE 1646 95 (2003)3included in the test specimen, and the interior support must beable to slide parallel to the panel or its attachment or both.8.2 If insulation is an optional component of the roofsystem,
39、 it shall not be included in the test specimen.8.2.1 If only one specimen is to be tested, the specifyingauthority determines the selection.NOTE 6It should be recognized that performance is likely to be afunction of size, geometry, and stiffness. Therefore, select specimenscovering the range of size
40、s to be used in a building. In general, the largestsize and least stiff of a particular design, type, construction, and configu-ration should be tested (see Note 2 for related commentary).8.3 Overflow devices shall be provided to ensure that waterponds at least12 in. (13 mm) but no more than34 in. (
41、20 mm)above the panel bottom between each major flute while thespecimen is subjected to the specified flow.9. Calibration9.1 The ability of the test apparatus to meet the require-ments of 6.2.4.1 shall be checked by using a catch box, theopen face of which shall be located at the position of the fac
42、eof the test specimen. The calibration device is illustrated in Fig.2. The catch box shall be designed to receive only waterimpinging on the plane of the test specimen face and to excludeall run-off water from above. The box shall be 24 in. (610 mm)square and divided into four areas each 12 in. (305
43、 mm) square.Use a cover approximately 30 in. (760 mm) square to preventwater from entering the calibration box before and after thetimed observation interval. The water impinging on each areashall be captured separately. A spray that provides at least 20gal/h (1.26 L/min) total for the four areas an
44、d not less than 4gal/h (0.25 L/min) nor more than 10 gal/h (0.63 L/min) in anyone square shall be acceptable.9.1.1 The water-spray system shall be calibrated at allcorners and, if no overlapping occurs, at the quarter andmid-points of the horizontal center line (of the spray system).If a number of i
45、dentical, contiguous, modular spray systems areused, only one module is required to be calibrated. The systemshall be calibrated with the catch boxes at a distance within 62in. (50 mm) of the required test specimen location relative tothe nozzle. Recalibration shall be at intervals necessary in thej
46、udgment of the testing agency but not longer than 6 months.10. Information Required10.1 The test-pressure difference or differences at whichwater penetration is to be determined, unless otherwise speci-fied, shall be 2.86 lbf/ft2(137 Pa) for roof applications less thanor equal to 30 from horizontal.
47、 Unless otherwise specified,this test-pressure shall be 20 % of the positive design windpressure but not less than 6.24 lbf/ft2(300 Pa) for roofapplications steeper than 30 from horizontal. The test pressureshall not exceed 12 lbf/ft2(575 Pa).NOTE 7This commentary is included to assist the specifier
48、 in theselection of test pressures. This test method is consistent with the defaulttest-pressure in Test Method E 331 and the recommendations in AAMAMethods 501. This test method considers that although neither is tolerable,water penetration at roofs is generally even less acceptable than at walls.
49、However, for shallow roofs, the test pressure requirement is bufferedsince these roofs rarely see large positive pressures unless the resultantpressure is caused by building openings. The default test pressure in TestMethod E 331 has been adapted for low sloped roofs. Positive pressuresare more probable at steeper slopes. Most model codes recognize this, and30 from horizontal is generally selected as the slope above which positiveexternal wind pressures must be considered. This test method selects the30 slope as its break point and adopts the AAMA 501 test p