1、Designation: D 6705 04Standard Guide forRepair and Recoat of Spray Polyurethane Foam RoofingSystems1This standard is issued under the fixed designation D 6705; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. 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 covers the procedures for the repair andrecoating of existing spray polyurethane roofing systems.1.2 The values state
3、d in SI units are to be regarded as thestandard. The values in parentheses are for information only.1.3 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 heal
4、th practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 1029 Specification for Spray-Applied Rigid CellularPolyurethane Thermal InsulationD 5469 Guide for Application of New Spray Applied Poly-urethane Foam and Coated Roofing
5、SystemsD 6083 Specification for Liquid Applied Acrylic CoatingUsed In Roofing2.2 SPFA Standards:3AY 102 A Guide for Selection of Elastomeric ProtectiveCoatings Over Sprayed Polyurethane FoamAY 107 Spray Polyurethane Foam Blisters, Their Causes,Types, Prevention and Repair2.3 API Standard:4Alliance f
6、or The Polyurethane Industry (API), Bulletin AX119 Guide for Safe Handling and Use of Polyurethaneand Polyisocyanurate Foam Systems3. Terminology3.1 Definitions:3.1.1 recoatto apply a new protective coating over anexisting coated SPF (spray polyurethane foam) roof system toextend the performance lif
7、e of the roofing system.3.1.2 scarfingto shave or grind an SPF foam surfacemechanically to remove a coating, or UV deteriorated SPF, orboth, to refoam or recoat the surface.4. Significance and Use4.1 This guide outlines general procedures and precautionsnecessary for correct and safe repair and reco
8、at of SPF roofingsystems.4.2 This guide is not all inclusive; this guide is intended tosupplement detailed instructions from manufacturers andsafety requirements required by law.5. Roof Inspection Procedures and Considerations5.1 General Considerations:5.1.1 The performance of a sprayed-in-place pol
9、yurethanefoam roof system can be affected by all the component parts ofthe roof structure, as well as the atmospheric conditions insideand outside the structure. Structural design, code compliance,specification review, contractor, and material selection shouldbe considered in the repair and recoat o
10、f a spray polyurethanefoam roof system.5.1.2 A range of spray polyurethane foam systems existswith various physical properties, exhibiting different tempera-ture limitations, and different combustibility characteristics.Most published data are obtained from testing of laboratorysamples. The thicknes
11、s of the polyurethane foam sprayed,number of passes, temperature of substrate, ambient tempera-ture, and so forth will have an effect on all polyurethane foamproperties.5.1.3 The specifier should consult with the respective ma-terial manufacturer of the sprayed-in-place polyurethane foamroof system.
12、 This should include, but not be limited to,materials selection, expansion joints, flashing details, and otheritems.1This guide is under the jurisdiction of ASTM Committee D08 on Roofing andWaterproofing and is the direct responsibility of Subcommittee D08.06 on SprayPolyurethane Foam Roof Systems.C
13、urrent edition approved Dec. 1, 2004. Published December 2004. Originallyapproved in 2001. Last previous edition approved in 2001 as D 6705 01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards vo
14、lume information, refer to the standards Document Summary page onthe ASTM website.3Available from Spray Polyurethane Foam Alliance, 4400 Fair Lakes Ct., Suite105, Fairfax, VA 22033.4Available from TheAlliance for the Polyurethanes Industry, 1300 Wilson Blvd.,Arlington, VA 22209.1Copyright ASTM Inter
15、national, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 Inspection:5.2.1 The preparation for the repair and recoat of a sprayed-in-place polyurethane foam roof system will vary according tothe conditions of the roof and its component parts and the typeof exi
16、sting protective coating used over the polyurethane foam.5.2.2 Conduct a roof inspection to determine the repairs tobe performed and the type of materials to be used.5.3 Visual Inspection:5.3.1 Look for blisters or delaminated areas in the originalroof.5.3.2 Check the condition of the roofing system
17、 at allflashing and termination points.5.3.3 Look for damage that would affect recoating of theroofing system.5.3.4 Check for pinholes in the polyurethane foam, orcoating, or both.5.3.5 Check for exposed polyurethane foam and areas oferoded coating.5.3.6 Check for areas of ponding water.5.4 Physical
18、 Inspection:5.4.1 Perform a nondestructive moisture survey. Follow upsuspected moisture-laden areas with a moisture probe or coresamples.5.4.2 Take slit samples of the existing system as required bythe new coating manufacturer.5.4.3 Take polyurethane foam core samples as required bythe SPF, or coati
19、ng manufacturer, or both.5.5 Analyze Inspection:5.5.1 Core and slit samples should be examined for thefollowing characteristics:5.5.1.1 Adhesion of polyurethane foam to the substrate,5.5.1.2 Interlaminar adhesion of polyurethane foam,5.5.1.3 Presence of moisture,5.5.1.4 Adhesion of base coat to poly
20、urethane foam,5.5.1.5 Adhesion of top coat to base coat,5.5.1.6 Type and condition of protective coating, and5.5.1.7 Thickness of protective coating.5.5.2 On a roof sketch, indicate the following items anddeficiencies:5.5.2.1 Location of core and slit samples,5.5.2.2 Areas of pinholes,5.5.2.3 Uncure
21、d coating,5.5.2.4 Polyurethane foam or coating blisters,5.5.2.5 Mechanical damage,5.5.2.6 Poor drainage,5.5.2.7 Repairs required for foamstops, parapet walls, gut-ters, scuppers, edge-termination details, expansion joints,counterflashing, and other perimeter items,5.5.2.8 Repairs required to soil an
22、d vent pipes, drains, roofhatches, equipment curbs or supports, guy wires, hot stacks,skylights, mechanical units, walkways, sleepers, pitch-pans,and other penetration items,5.5.2.9 Water-saturated subroofs, insulation, or polyure-thane foam,5.5.2.10 Subroof damage or deterioration, and5.5.2.11 Area
23、s of special consideration.6. Selection of Primer6.1 A primer may be required to enhance adhesion of thenew coating to the existing coating. The recommendations ofthe new coating manufacturer shall be used to determineprimer requirements.7. Selection of Protective Coatings7.1 The following must be t
24、aken into consideration whenchoosing a recoating material:7.1.1 Perm rating required according to the vapor drivepotential,7.1.2 Compatibility with the existing roof coating,7.1.3 Specifiers, or manufacturers, recommendations, orboth,7.1.4 Environmental conditions,7.1.5 Slope limitations, and7.1.6 A
25、nticipated mechanical abuse.7.2 Refer to SPFA AY 102 and Specification D 6083 forinformation on protective coatings used over SPF roofingsystems.8. Selection of the Polyurethane Foam System8.1 New applied spray polyurethane foam must be compat-ible with the existing system and comply with polyuretha
26、nefoam Type III or IV, as defined in Specification C 1029.9. Execution9.1 General:9.1.1 The polyurethane foam and coating shall be applied incompliance with Guide D 5469.9.2 Surface Preparation and Repair:9.2.1 From the inspection, list items that need correction.9.2.2 Determine if a primer is requi
27、red (see Section 5).9.2.3 Remove or repair unacceptable substrate.9.2.4 Remove and replace blistered polyurethane, followingthe procedure outlined in SPFA AY 107.9.2.5 Remove unacceptable coating. Consult the coatingmanufacturer for recommended removal method.9.2.6 Apply coating at recommended thick
28、ness to repairedareas. Two or more coats should be used. The final dry milthickness of repaired areas should be specified.9.2.7 Small (less than 200-mm (4-in.) blisters, cracks,breaks in the foam or coating, bird pecks, or hail damage canbe repaired with a compatible sealant when the sealant is:9.2.
29、7.1 Not installed in a greater area or thickness than isrecommended by the manufacturer for proper cure,9.2.7.2 Installed so as to ensure the final surface is higherthan the surrounding area so that water will not remain on therepair area, and9.2.7.3 The type of sealant recommended by the coatingman
30、ufacturer.9.2.8 The area to be repaired should be significantly cleanand the edges beveled to assure proper adhesion.9.2.9 In some cases, foam-core plugs can be used withsealant to make small repairs. Foam-core plugs must be of thesame density as the foam they are replacing.9.2.10 If weathering has
31、caused the surface of the coatingand the foam to degrade (pitting), such a surface should bescarfed to expose clean, dry polyurethane foam.D67050429.2.11 To eliminate ponding:9.2.11.1 Install additional roof drains or scuppers.9.2.11.2 Build up low areas by applying polyurethane foam.Follow the manu
32、facturers recommendation for surface prepa-ration.9.2.12 Repair or replace deteriorated flashing, roof jacks,metal work, curbs, supports, penetrations, drains, and so forth.9.2.13 Clean the existing coated roof surface of contami-nants that could affect adhesion by power washing, brooming,scarfing,
33、or blowing, or both, as recommended by the coatingmanufacturer.9.3 Protective Coating Application:9.3.1 General Coating Requirements:9.3.1.1 The existing coating and repaired polyurethane foamshall be free of contaminates that could affect adhesion and UVdegradation.9.3.1.2 The texture of the foam w
34、ill influence the amount ofcoating material required.9.3.1.3 Apply one or more applications of the coating overthe entire SPF roof system at a uniform rate so as to obtain theminimum dry-film thickness specified by the coating manufac-turer.9.3.2 Inspection:9.3.2.1 The coating shall be allowed to cu
35、re and be in-spected for pinholes, thinly coated areas, uncured areas, orother defects. Any defects should be repaired before subse-quent applications. The base coat shall be free of contaminantsthat could affect adhesion before application of the topcoat.9.3.2.2 Subsequent coating, if required, sho
36、uld be applied ina timely manner to ensure proper adhesion between coats.9.4 Granule Application (Optional):9.4.1 Shall be of the size and type and applied in the topcoatas recommended by the coating manufacturer.9.5 Walkways:9.5.1 Walkways may be installed for heavy traffic areas andaround frequent
37、ly serviced roof top units. Breathable walkpads should be used as recommended by the coating manufac-turer.10. Safety Requirements10.1 All handling, storage, applications, and end-use safetyprecautions shall be as outlined by the material manufacturersand API AX 119.10.2 Refer to appropriate materia
38、ls safety data sheets(MSDS) for additional safety information. (WarningBeforestarting to apply spray polyurethane foam or coating, all HVACequipment on the roof must be turned off. These units and anyother potential sources of air entry into the building must besealed.)10.3 Conform to local codes an
39、d ordinances.11. Keywords11.1 polyurethane foam; repair and recoat; roofing systems;SPFASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of
40、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 every five years andif not revised, either reapproved or withdrawn. Y
41、our 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 technical committee, which you may attend. If you feel that your commen
42、ts 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 Conshohocken, 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).D6705043
