Seismic Technical GuideTechnicalDocumentCompression PostsUSG Donn Brand Compression Post provides rigid support for a ceilingsuspension system in seismic applications. Telescoping compression postsattach to the main tees at each splayed wire location, preventing upwardmovement of the system, often required by code. Because codes continue toevolve1, check with a local official prior to designing and installing a ceilingsystem.Features– F actory-engineered solution provides system rigidity in seismic applications and offers quick installation thusreducing field labor time.– Availabe in six different telescoping sizes that meet requirements and includes fast delivery.Item No.VSA 18/30VSA 30/48VSA 48/84VSA 84/102VSA 102/120VSA 120/144Size189 to 309309 to 489489 to 849849 to 10291029 to 12091209 to 1449– Injection-molded, high-impact clip snaps onto the bulb of the main tee for a secure, positive connection.–––––Heavy-wall galvanized steel tubing, no-rust telescoping post locks into permanent support length.Injection-molded guide ring prevents rattling.Spring steel top clip for attachment to vertical hanger wire adjacent to postThe adjustable self-locking connection has been tested and certified to a minimum compressive load of 900 lb.Meets UL797End PlugTop ClipComponents1See last page for Seismic CodeReference StandardsNote: All components are included with each postHanger WireSpring ClipSpring Clip AttachmentHoles (Top of Post)

InstallationApplicationStep 1Fit top clip into the opening of the post.Step 2Snap compression post onto main tee bulb next to vertical hanger wire.Step 3Bring compression post to vertical with hanger and extend post for snug fit against structure.Step 4Loop spring clip around vertical hanger wire and connect to holes on top of post.Step 5Mechanically fasten end plug of post to main tee bulb.Step 6Fasten compression post to structure with the appropriate mechanical clip(mechanically fastened)structurespring clipspring clipattachment holesvertical hangerwire adjacentto postspring clipinserts inhole in poststructuretop clipsplay wire securedto structurehanger wire45 or less45 or less45 or less45 or lessbulb clip(mechanically fastened)compression postceiling cross teeinstall within2" of cross teeintersectionspring clipinserts inhole in postvertical hangerwire adjacentto poststructuresplay wire securedto structure45 or less45 or less45 or less45 or lesscross tee2 Compression Postsinstall within2" of cross teemain teemain tee2" max.2" max.a fastener or splay wiresmaybe inserted into thetab of the post andthrough a conveniencehole in the main tee bulb

InstallationAlternative MaterialsT he USG Donn Brand compression post is an engineered solution designed to work with USG Donn Brand Suspension Systems when required by code.The USG Donn Brand compression post is an option for almost every project, however it is not necessary to use the USG Donn Brand compression postwhen installing USG Donn Brand Suspension Systems. Any steel member with sufficient strength is allowed by code and may be suitable for use as acompression post. Below are some common, light gauge steel members provided by others that are typically used as alternates for compression postsand their typical associated allowable lengths.Alternative MaterialTypicalAllowable LengthAlternative MaterialTypicalAllowable Length13/169 x 13/329 Strut 19 GA2493-5/89 x 1-1/49 18GA Stud (362S125-43)8491-1/29 x 9/169 x 0.0599 Channel3391-1/49 x 1-1/49 Strut 14 GA849(2) 3/49 x 1/29 x 0.0599 Channel, Back to Back3993-5/89 x 1-1/49 20GA Stud (362S125-30)859(2) 1-1/29 x 9/169 x 0.0599 Channel, Back to Back4492-1/29 x 1-1/49 25GA Stud (250S125-18)8791/29 Diameter EMT Conduit, 0.0429 Wall Thickness479158STS 1-5/89 x 1-1/49 x 0.01979 Channel9093/49 x 1/29 x 0.0599 Channel4791-3/89 x 1-5/89 Strut 12 GA96913/169 x 1-5/89 Strut 12 GA4891-1/49 x 2-1/29 Strut 14 GA96913/169 x 1-5/89 Strut 14 GA4891-5/89 x 1-3/89 Strut 12 GA9691-1/49 x 3/49 Strut 14 GA4891-1/49 Diameter EMT Conduit, 0.0659 Wall Thickness10291-1/49 x 5/89 Strut 19 GA4891-5/89 x 1-5/89 Strut 14 GA10891-5/89 x 13/169 Strut 14 GA4891-5/89 x 1-5/89 Strut 12 GA10891-5/89 x 13/169 Strut 12 GA4891-1/29 Diameter EMT Conduit, 0.0659 Wall Thickness118913/169 x 13/169 Strut 19 GA5493-1/49 x 1-5/89 Strut 12 GA120919 x 1-5/89 Strut 12 GA6092-7/169 x 1-5/89 Strut 12 GA12091-5/89 x 7/89 Strut 12 GA6091-5/89 x 1-5/89 Strut 16 GA12091-5/89 x 13/169 Strut 16 GA6091-5/89 x 3-1/49 Strut 12 GA12091-5/89 x 19 Strut 12 GA6091-5/89 x 2-7/169 Strut 12 GA12093/49 Diameter EMT Conduit, 0.0499 Wall Thickness619(2) 158STS 1-5/89 x 1-1/49 x 0.01979 Channel, Back to Back130919 Diameter EMT Conduit, 0.0579 Wall Thickness78929 Diameter EMT Conduit, 0.0659 Wall Thickness15093-5/89 x 1-1/49 16GA Stud (362S125-54)829Notes1. The information provided is for quick reference only. Other restrictions and exemptions may apply.2. All struts and allowable lengths should be verified by a design professional before use.3. Wind loads may exceed seismic loads. The distances above may not be suitable for exterior use.4. Wall molding should not be used as struts.5. A structural engineer should be consulted for lengths greater than 14ft.Compression Posts 3

ComplianceCode Compliance– ICC-ESR-1222– City of Los Angeles Research Report: RR25764–C A Division of the State Architect (DSA) IR-A5 Interpretation of Regulations Manual through referenceto ICC-ESR-1222 or CA Division of the State Architect (DSA) IR-A6 Change Order and Field ChangeApproval Processes.–C A Office of Statewide Health Planning and Development (OSHPD) please refer to Code ApplicationNotice 2-1708A.5, pre-approval through ICC-ESR-1222 is recommended.

Seismic Code Reference StandardsInstallation Guidelines for Suspended Ceilings International Building Code (IBC)2003 IBC2006 IBC2009 IBC2012 IBCAmerican Society of Civil Engineers (ASCE)ASCE7-02ASCE7-05ASCE7-05ASCE7-10CISCA Zones 0-2CISCA Zones 0-2CISCA Zones 0-2ASTM E580CISCA Zones 3-4CISCA Zones 3-4CISCA Zones 3-4Ceilings Interior Systems ConstructionAssociation (CISCA)orASTM International (ASTM)International Building Code (IBC) defines Seismic Design Categories A, B, C, D, E, and F.www.iccsafe.orgASCE/SEI 7 Minimum Design Loads for Buildings and Other StructuresAmerican Society of Civil Engineers/Structural Engineer Institute (ASCE/SEI)www.asce.orgGuidelines for Seismic Restraint for Direct-hung Suspended Ceiling Assemblies (Zones 3-4)Recommendations for Direct-hung Acoustical Tile and Lay-in Panel Ceilings (Zones 0-2)CISCA Ceilings & Interior Systems Construction Association (CISCA)www.cisca.orgASTM Internationl E580/E580M Standard Practice for Installation of Ceiling Suspension Systemsfor Acoustical TIle and Lay-in Panels in Areas Subject to Earthquate Ground Motions.ASTM International (formerly American Society for Testing and Materials)www.astm.orgFurther ReferencesUSG Seismic Ceiling Resource CenterSeismic Technical Guidesseismicceilings.comProduct InformationPurposeSee for the mostThis seismic technical guideup-to-date product information. (STG) is intended as a resourcefor design professionals, toInstallationpromote more uniform criteriaMust be installed in compliance for plan review and jobsitewith ASTM C636, ASTM E580, inspection of projects. ThisCISCA, and standard industrySTG indicates an method for achievingcompliance with applicableCode Compliancecodes and regulations, althoughThe information presented isother methods proposed bycorrect to the best of our knowldesign professionals may beedge at the date of issuance.considered and adopted.Because codes continue toevolve, check with a local official ICC Evaluation Service, Inc.,prior to designing and installing Report Compliancea ceiling system. Other restric- Suspension systems manutions and exemptions may apply. factured by USG Interiors, Inc.,This is only intended as a quick have been reviewed and arereference.approved by listing in ICC-ESEvaluation Report ESR-1222.Evaluation Reports are subjectto reexamination, revision andpossible cancellation. Pleaserefer to usgdesignstudio.comor for current reports.Manufactured byUSG Interiors, LLC550 West Adams StreetChicago, IL .comusgdesignstudio.comL.A. Research ReportComplianceDonn brand suspension systemsmanufactured by USG Interiors,Inc., have been reviewed andare approved by listing in thefollowing L.A. Research Reportnumber: 25764.NoticeWe shall not be liable forincidental and consequentialdamages, directly or indirectlysustained, nor for any losscaused by application of thesegoods not in accordance withcurrent printed instructions orfor other than the intended use.Our liability is expressly limited toreplacement of defective goods.Any claim shall be deemedwaived unless made in writingto us within thirty (30) days fromdate it was or reasonably shouldhave been discovered.Safety First!Follow good safety/industrialhygiene practices duringinstallation. Wear appropriatepersonal protective equipment.Read MSDS and literaturebefore specification andinstallation.The following are trademarks of USGInteriors, Inc. or a related company:Donn, DX, DXL, USG in stylized letters.SC2497/rev. 2-12 2012, USG Interiors, LLCPrinted in U.S.A.

splay wire secured to structure main tee cross tee install within 2" of cross tee intersection a fastener or splay wires maybe inserted into the tab of the post and through a convenience hole in the main tee bulb 2" max. 2" max. vertical hanger wire adjacent to post 45 or less 45 or les