1、Designation: C 1487 02 (Reapproved 2007)Standard Guide forRemedying Structural Silicone Glazing1This standard is issued under the fixed designation C 1487; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、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 guide provides recommendations for remedyingexisting structural sealant glazing (hereinafter called SSG)installations in situ.
3、Remedial work may be necessary when alite of glass is replaced, for routine maintenance, or afterdistress is discovered. This guide focuses on large-scaleremedies.1.2 Committee C24 is not aware of any comparable stan-dards published by other organizations.2. Referenced Documents2.1 ASTM Standards:2C
4、 717 Terminology of Building Seals and SealantsC 1392 Guide for Evaluating Failure of Structural SealantGlazingC 1394 Guide for In-Situ Structural Silicone Glazing Evalu-ationC 1401 Guide for Structural Sealant GlazingE 330 Test Method for Structural Performance of ExteriorWindows, Doors, Skylights
5、and Curtain Walls by UniformStatic Air Pressure DifferenceE 997 Test Method for Structural Performance of Glass inExterior Windows, Curtain Walls, and Doors Under theInfluence of Uniform Static Loads by Destructive MethodsE 1233 Test Method for Structural Performance of ExteriorWindows, Doors, Skyli
6、ghts, and Curtain Walls by CyclicAir Pressure Differential3. Terminology3.1 DefinitionsDefinitions of the terms used in this guideare found in Terminology C 717.3.2 Definitions of Terms Specific to This Standard:3.2.1 distress, nthe individual or collective physical mani-festations of a failure as p
7、erceivable problems. For structuralsealant glazing, such distress may include sealant adhesivefailure, sealant cohesive failure, shifting of a lite, loss of a lite,or water infiltration (see Guide C 1394).3.2.2 qualified person, none with a recognized degree orprofessional registration and extensive
8、 knowledge and experi-ence in the field of structural sealant glazing, and who iscapable of design, analysis, and evaluation in the subject.4. Significance and Use4.1 Guidelines are provided for remedying existing SSGinstallations. Refer to Guide C 1401 for a complete discussionof proper SSG design,
9、 installation, and materials.4.2 Due to the unlimited range of materials that may be usedin a particular building, and because each design is unique, theinformation contained in this guide is general in nature.4.3 This guide should not be the only reference consultedwhen designing remedies for SSG.
10、For example, the localbuilding code and the manufacturers product literature for theactual materials used, if known, also should be considered. Thesealant manufacturer(s) should be involved fully with theremedial design.4.4 This guide is intended to be a resource, but it is not asubstitute for exper
11、ience and judgement in designing remediesfor the specialized types of construction discussed. It isintended to be used in conjunction with other resources as anaid in remedying problems with existing SSG.5. Introduction5.1 There are numerous reasons that a building owner ormanager, hereinafter refer
12、red to as owner, may choose toremedy an SSG system, including routine maintenance or tocorrect discovered deficiencies. Regardless of the reason thatsuch a remedy is undertaken, it is recommended that theremedial design and construction be performed under thesupervision of a qualified person.5.2 It
13、is essential to begin the remedial process with acomprehensive evaluation, in accordance with the guidelinesestablished in Guide C 1394. The underlying cause of failuremust be understood fully prior to implementing a remedy;otherwise, the failure may be repeated.1This guide is under the jurisdiction
14、 ofASTM Committee C24 on Building Sealsand Sealants and is the direct responsibility of Subcommittee C24.10 on Specifi-cations, Guides and Practices.Current edition approved June 1, 2007. Published July 2007. Originally approvedin 2000. Last previous edition approved in 2002 as C 148702.2For referen
15、ced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West C
16、onshohocken, PA 19428-2959, United States.5.3 Based on the outcome of the evaluation, various rem-edies may be indicated. The potential remedies include, de-pending on the pervasiveness and the nature of the problem,the following:5.3.1 Isolated repairs (such as the replacement of an indi-vidual lite
17、 of glass) can be performed by a competent glaziertrained in the proper installation of SSG. If the original SSGwas properly performed, then such minor repairs can beeffected by careful duplication of the original procedures.5.3.2 In-situ remedial work is necessary where pervasiveproblems exist in a
18、n SSG application, such as due to poordesign or workmanship during original construction.5.3.3 Complete reglazing may be necessary in extremecases or at the end of the useful service life, in accordance withthe principles for new SSG. For example, if the existing jointconfiguration does not allow ad
19、equate cleaning to replace astructural joint, it may be necessary to reglaze, becauseadhesion is critical to the performance of SSG and cleaning iscritical to adhesion.5.4 The remainder of this guide particularly addresses thetype of in-situ remedial SSG projects as described in 5.3.2,tocorrect a pe
20、rvasive problem without comprehensive reglazing.6. Remedial Design6.1 If it is determined that a large-scale remedial program isnecessary, then a remedial design should be developed by aqualified person.6.2 Depending on the cause of the problem(s) with theexisting installation, it may not be prudent
21、 to rely on theoriginal SSG design.6.3 The remedial design should include the following:6.3.1 Calculations of the structural sealant stress so that thefinal installation will comply with the SSG industry guidelines(see Guide C 1401) and applicable codes. In some jurisdic-tions, glass replacement tri
22、ggers the requirement to complywith the current building code for glass strength and structuralsealant joint capacity, rather than the code under which thebuilding was originally constructed.6.3.2 Sealant product selection to be compatible with allexisting materials that it will contact.6.3.3 Access
23、ory product selection, if any are replaced oradded by the remedy, to be compatible with all existingmaterials that they will contact.7. Field Testing7.1 Prior to implementing the proposed remedial work, fieldtesting should be performed under the direction of a qualifiedperson. Whereas, in new SSG in
24、stallations it is possible toperform laboratory testing to verify the adhesion characteristicsof the products and substrates, remedial SSG usually requiresfield testing. In-situ adhesion testing is strongly recommendedfor the selected product combination, including cleaner,primer, sealant, and the a
25、ctual adhesion surface of the sub-strate.7.2 Field testing of the actual adhesion surface of thesubstrate is recommended, rather than another face of the samecomponent, because the adhesion characteristics may vary withexposure. It may be necessary to deglaze a lite to access theactual adhesion surf
26、ace. It is not recommended to test faces ofcomponents other than those actually scheduled for permanentadhesion because the adhesion characteristics can vary withexposure and manufacturing processes.7.3 Because the field test procedure may be cumbersomeand expensive to perform, it is recommended to
27、performpretesting to screen possible combinations of products. Thesepreliminary tests may be performed in the laboratory or in thefield on convenient surfaces of the components, rather than theactual adhesion surfaces.7.4 To verify adhesion with the final product combination,one field test procedure
28、 is as follows:7.4.1 Perform a minimum of three tests in selected mock-upareas. More tests should be performed depending on thereasons for repair, or if the existing conditions vary withexposure or other variables.7.4.2 Apply structural sealant and accessories to actualadhesion surfaces exactly as t
29、hey are intended to be installedduring full-scale production work.7.4.3 Adjust the installation so that the structural sealant isexposed, for example, a weatherseal joint may have to beomitted during testing.7.4.4 After the cure time recommended by the sealantmanufacturer, install chambers over the
30、test joints and adjacentsubstrates. Bed chambers in sealant and adhere to the face ofthe metal and glass, leaving the top open for filling. See Fig. 1.7.4.5 Fill the chambers with distilled water, causing the faceof the test joints to be completely immersed in water. Seal thetop edge of the chambers
31、 after filling, to prevent evaporation.In cold climates, consideration should be given to protectingthe chamber from freezing.7.4.6 After seven days water immersion, remove chambersand perform adhesion tests as prescribed by the sealantmanufacturer. Acceptance criteria should be determined by thesea
32、lant manufacturer.7.5 Finally, prior to proceeding with implementation of theremedial work, consideration should be given to performing afull-scale load test on representative mock-ups. These tests canbe performed using suction cups on the exterior or interior ofthe glass (Guide C 1392) or pressuriz
33、ed chambers on theinterior or exterior (Test Methods E 330, E 997,orE 1233).Such tests are often conducted at 1.5 times the design windservice load. Depending on the specific causes of failureidentified by evaluation (Guide C 1394), it may be appropriateto test individual components at different tes
34、t loads.8. Remedial Work8.1 Once a remedial program has been developed andtested, it is essential that the production work be implementedexactly like the approved mock-ups.8.2 It is important to recognize that most new SSG isperformed using shop-glazing methods, whereas remedial SSGtypically will re
35、quire field-glazing. It is more difficult tomaintain quality control procedures in the field, extra attentionshould be paid to monitoring the implementation, particularlyto ensure complete joint filling. Additional field testing also iswarranted. It is recommended that this monitoring and testingbe
36、performed by or under the direction of a qualified person.8.3 Even if it is generally expected that the specifiedremedial work will be practical at most locations, it is prudentC 1487 02 (2007)2to inspect each lite of glass and its opening before implement-ing the remedy for differing existing condi
37、tions, such aslocalized defects or dimensional variations. In particular, eachcrew should have a measuring device (check block) of fixedsize to determine whether the joint width is at least theminimum specified before sealing; commonly, such devices arefabricated for the project from wood, metal, or
38、 plastic. If thedevice does not easily fit into a joint along any 6 in. (or otherdimension specified) of joint length, then it should be reglazedin full compliance with the standards for new SSG.8.4 Care should be exercized to ensure that each glass lite issupported fully during the remedial work. O
39、ften, it is necessaryto stage the remedial work in phases so that the entire perimeterof a lite is not cut out at one time, and to use temporary clipsto retain the lites while the new structural sealant cures for thetime recommended by the sealant manufacturer.9. Documentation9.1 It is very importan
40、t that the remediation data be main-tained by the owner in a standardized format. It is recom-mended that the owner keep all evaluation and remediationreports in one notebook, along with other information pertinentto the SSG installation.9.2 The remediation report should provide the followinginforma
41、tion:9.2.1 Building identification, background information, andreferences to original design and construction firms.9.2.2 Purpose of remedy, including triggering event orreason.9.2.3 Deliniation of locations or areas where remedial workwas performed.9.2.4 Products used and test results.9.2.5 Recomme
42、ndations for further evaluation or remedialaction.NOTELegend:(1) Weather Seal (remove for testing, if required)(2) Spacer(3) Structural Sealant(4) Glass Lite or Panel(5) Metal Framing System(6) Test Chamber (sealed to face of wall, filled with water)FIG. 1 Schematic Diagram of Typical Field Water Im
43、mersion Test(Configuration May Vary for Different Structural Sealant Glazing Systems)C 1487 02 (2007)3BIBLIOGRAPHYDocuments Prepared by Manufacturers and TradeAssociations:(1) American Technical Manual, by Dow Corning Corporation(2) SSG Technical Guide, by Momentive Performance Materials (for-merly
44、GE Silicones)(3) Architectural Guidelines for Glazing Systems, by Tremco Corpo-ration(4) Curtain Wall Manual No. 13, Structural Sealant Glazing Systems(CW-13), AAMA(5) Two-Sided Structural Glazing Guidelines for Aluminum FramedSkylights, Item No. AAMA TSGG-91, AAMABooks:(6) Klosowski, J.M. Sealants in Construction, Marcel Dekker, Inc.,1989.(7) Panek, J. R. and J.P. Cook, Construction Sealants and Adhesives,John Wiley or through the ASTM website(www.astm.org).C 1487 02 (2007)4
