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Technical 12/13
<br /> Document figure 2
<br /> NWC• Lateral force Bracing Lateral Force Bracing(rlgure9zand3)
<br /> SUSPENDED CEILINGS - Ceilings constructed of screw-or-nail-attached gypsum board on
<br /> one level that are surrounded by and connected to walls or soffits
<br /> Design a s '"°' "°'^` that are laterally braced to the structure above are exempt from n
<br /> Ceiling areas of 1000 ft°or lase shall be exempt from later force seismic design requirements. �I ',I
<br /> l.oa 111111111111
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<br /> This document has been revised based on current Building Code standards.In all buildings,otherthan structures Gassifietl as "°"°` "°'° bracing requirements.s:�.ce As*r<Esez
<br /> essential facilities,suspended ceilings installed in accordance with the prescriptive provisions of the 401 document are
<br /> deemed to comply with the current building code interpretation. Lateral force bracing is the use of vertical struts(compression
<br /> This document provides the IBC-2012 referenced standards for the installation of suspension systems for acoustical lay-in cm°°'_= m=e==m posts)and splay wires(see figure 2). 950 1ST STREET SOUTH
<br /> ceilings.Incorporation of this document will provide a more uniform standard for installation and inspection.This document is Lateral Force Bracing shall be 12 feet on center(maximum)and Kill WA 98033
<br /> designed to accomplish the intent of the International Building Code(IBC)whh regard to the requirements for seismic design figure 3 begin no farther than 6 feet from walls.so As,=: :425.827.7850
<br /> category D,E and F for suspended ceilings and related items.Unless supported by engineering,the suspension system shall be Maximum Recommended Lengths for Seismic splay wires are to be four 12 gage wires attached to the TEL TEL:425.827.7850
<br /> installed per these requirements and those of the referenced documents.Manufacturers'recommendations should be followed Vertical Struts main beam.Wires are arrayed 90'from each other and at an INFOOPAGEANDBEARD.COM
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<br /> where applicable. angle not exceeding 45°from the plane of the ceiling.
<br /> h"EMT conduit UP to 5'10, Seismic splay wires shall be attached to the grid and to the
<br /> M."EMT conduit up to TO" structure in such a manner that they can support a design load of
<br /> not less than 200 pounds or the actual design load,with a safety
<br /> V EMT conduit up to W9" factor of 2,whichever is greater(figure 6b).s_. - -.
<br /> • Power Actuated Fasteners(PAF's),when used for seismic
<br /> Single IW metal stud(20 gage) up to 12'0" application as part of the prescriptive path in Seismic Design
<br /> Categories D,E and F,shall have an ICC-ES approval for seismic
<br /> sack-to-back 1'A"metal stud up to 160" applications and shall require"special inspection'irrespective of
<br /> (20 gage) the type of occupancy category the structure is in.PAF anchors
<br /> Single 2''A"metal stud(20 gage) up to 13'6" for kicker wires(splayed Wires Installed for purposes other than
<br /> seismic restraint)are exempt from this requirement.
<br /> Back-to-back 2 W-mewl stud(26 gage) up to 15'0"
<br /> sou,*vomand eunbmg Deaarcma„ Splay wires are to be within 2 inches of the connection of the
<br /> mom P,e,um areas groan,me"15 c,wmrewlre el,m..g vertical strut to suspended ceiling.s::,ce ASna Es50 secho,s z e z is
<br /> General Recommendations camma,o,s. Rigid bracing may be used in lieu of splay wires.$1,11,AST E580
<br /> • Referenced sources per hierarchy:2012 International Building Code(IBC),American Society of Civil Engineers figure 4a se-, _
<br /> (ASCE 7.10),American Society of Testing Materials(ASTM C 635,ASTM C 636,ASTM E 580/E 560M),and Attached Wall Molding Requirements Ceilings with plenums less than 12 inches to structure are not
<br /> Ceilings and Interior Systems Construction Association(CISCA). required to have lateral farce bracing.some P,aa Dapa4mao, W
<br /> • Partitions that are tied to the ceiling and all partitions greater than 6 feet in height shall be laterally braced to the Vertical struts must be positively attached to the suspension z
<br /> structure.Bracing shall be independent of the ceiling splay bracing system.source.AscE systems and the structure above....,ASTM E560 Sacho,s z ea
<br /> • For further information on bracing of non-load bearing partitions refer to NWCB Technical Document#200501. 0 The vertical strut may be EMT conduit,metal studs or a proprietary ~I M
<br /> • All main beams are to be Heavy Duty(HD).S-11 ASr ESSO Sarno,s.r: 0 0" compression post(see figure 3). 2
<br /> • Ceilings less than or equal to 144 ft°and surrounded by walls connected to the structure above are exempt from '•a Wall Moldings U� >� 00
<br /> the seismic design requirements.souse ASTM E590 sacs„14 g (agunsa4eend�D) v (3)
<br /> • These recommendations are intended for suspended ceilings and related Wall moldings(perimeter closure angles)are required to have a (n
<br /> components In areas that require resistance to the effects of earthquake motions. horizontal Flange 2 inches wide.One end of the ceiling grid shall Q L j
<br /> So—ASr IFUO 511 rlgure 4b be attached to the wall molding,the other end shall have a a/.inch 4--r
<br /> • All wire ties are to be three tight turns around itself within three inches.Twelve gage Unattached Wall Molding Requ,-. clearance from the wall and free to slide. O
<br /> Sacs::°5 2 e CO
<br /> Hanger wire spaced 4 foot on ce
<br /> nter(figure 1).source.AS C636 sec-c--- '" )Il I�.
<br /> • Changes in ceiling planes will require positive bracing.Sol,,,ASTM eseo sac:,,52 a 5 ..,-, , Where substantial documentation has been provided to the J O w
<br /> local jurisdiction,perimeter clips may be used to satisfy the CK
<br /> requirements for the 2-inch closure angle. LLl
<br /> W W
<br /> figure 1 � The grid shall be attached at two adjacent walls(pop rivets or
<br /> ,;, •°-••^•° '^^ approved method).Soffits extending to a point at least level
<br /> PAGE 1 OF 4 with the bottom plane of the grid and independently supported
<br /> EXTEND HANDRAIL I,
<br /> HigherBuild to a and laterally braced to the structure above are deemed to be Q
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<br /> MIN OF 12" 2825 Eastlake Ave E Ste 350 1 Seattle,WA 98102 tel 503-295-0333 '---
<br /> BEYOND THE TOPP tal 206-524-42431*mall,nfo@nwcb.org email Oregon@nwcb.org
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<br /> figure 5a equivalent to wells.Souma's orogon.Bu;ICing co0ea Divis;on.ASTM E580 SeO, figure 7 The layout and location of the seismic separation
<br /> z joint shall be per the designer of record and noted on
<br /> Spreader Bars!sure ab) the plans.If a seismic separation joint is required by
<br /> the designer,the designer may use the genericjoinl
<br /> • Terminal ends of main runners and cross members shall be tied - detailed in this document or a proprietary joint.The
<br /> together or have some other approved means to prevent their amount of free movement(gap design)shall be a
<br /> spreading.Stabilizer bars,cross tees or other means to prevent minimum of/.inch.:-
<br /> spreading shall occur within 8 in,of each wall. _ .E_ _s c,,..._...,
<br /> -- - Spreader bars are not required at perimeters where runners are ,,, '"°' In lieu of seismic separation joints,the ceiling maybe
<br /> attached directly to closure angles. '^^^'^ divided into areas less than 2600 square feet by the use
<br /> • Spreader bars are not required if a 90 degree intersecting cross or main Terminals or services weighing 20 lbs.but not more of partitions or soffits as follows:partitions shall extend a
<br /> rgwe so•C...te,slopi,g is within 8 inches of the perimeter wall. than 56 lbs.shall have,in addition to 5.4.1,two 12 gage minimum of 6 inches above the level of the plane of the PERMIT
<br /> • Where substantiating documentation has been provided to the local wires connecting them to the ceiling system hangers or gird and shall be independently braced to the structure SET
<br /> •'* jurisdiction,perimeter Gips may be used to satisfy the requirements for the structure above.These wires may be slack.sit::: above.Soffits shall extend to a point at least level with
<br /> spreader bars.sc".ca sure oronggn.Bo;im,..c::.s=--; A .eseo secto s-- the bottom plane of the grid and shall be independently JOB NO: 19.63
<br /> •_•^•• •_•^_^ Terminals or services weighing more than 56 IDS.shall supported and laterally braced to the structure above. 6suE DATE
<br /> 2%TOP PLATE Hanger(Suspension)Wires(6garee 5.and So) be supported directly from the structure above by
<br /> • Hanger and perimeter wires must be plumb within 1 in 6 unless(figure 5a) approved hangers.s�cu=s-,sses s;r,=s-= 01 PERMIT sler 2II9/0020
<br /> counter sloping wires are provided(figure 5b). Sprinklers
<br /> Hanger wires shall be 12 gage and aced 4 feet on center or 10 gage Seismic Separation Joints(agure�)
<br /> 9 9 9 P 9 9 For ceilings without rigid bracing,sprinkler head
<br /> spaced 5 feet on center. �srr:ca;, For ceiling areas exceeding square feet,a penetrations shall have a 2 inch oversize ring,sleeve or
<br /> figure sit seismic separation joint or full11 height wall partition that
<br /> • Any connection device at the supporting construction shall be capable breaks the ceiling shall be provided unless analyses adapter through the ceiling file to allow free movement of are performed of the ceilings bracing system,closure
<br /> of carrying not less than 100 pounds.: at least 1 inch in all horizontal directions.Flexible head
<br /> v.roe.i hana•rwiro awrBm.m
<br /> • Powder Actuated Fasteners(PAFs)are an approved method of angles and penetrations to provide sufficient clearance. design that can accommodate 1 inch free movement shall
<br /> s m°' - -_ li sx• attachment for hanger wires. B:rpe c: s - - be permitted as an alternate
<br /> np` .. Terminal ends of each main beam and cross tee must be supported
<br /> within 8 inches of each wall with a perimeter wire(see figure 4 8 5 a).
<br /> o ma Glossary for this Document(regional terminology may vary)
<br /> • Wires shall not attach to or bend around interfering material or
<br /> 4X4 DF#1 v— ge ,° _ equipment.A trapeze or equivalent device shall be used where CROSS TEES The cross member that interlock with the main perimeter ends of an accoustical ceiling grid.
<br /> EXISTING DEM15ING WALL obstructions preclude direct suspension.Trapeze suspensions shall
<br /> GUARDRAIL POST beams,also known as cross runners or cross T-bars.
<br /> ®48"oc MAX. be sized to resist the dead load and lateral forces appropriate for the PERIMETER CLIPS Proprietary angle which
<br /> alto attached directly move-
<br /> is DOCUMENT o BY E As ArtorueT.k
<br /> - --' seismic Category.:.. .._:_...r. DIFFUSER A circular or rectangular metal grill used for the to the wall molding/closure angle which allows for a/.°move-
<br /> peasage of air from a ducted system. meet in the event of seismic activity and interlocks properly IAo moue SET ON Onoiec'i oa on
<br /> apieyaa seismic Bracing wi.e anacnmank ESSENTIAL SERVICE Btii'-'"-=�qny buildings designed to be with ends d69tem, rumor or rxrs Pamen ev mx
<br /> Electrical fixtures 9n v �aopAGese A0.CHN�P5111N
<br /> emu axpa,mo,I-., Light fixtures weighing less than 10 pounds shall have one 12 gage used by public agencies as a fire station,police station,emer- PERIMETER WIRES Hanger wires placed within eight inches of
<br /> ro ro"O°° hanger wire connected from the fixture to the structure above.This wire agency operations center,State Patrol office,sheriffs office,or the surrounding walls.
<br /> mergency communication dispatch center.
<br /> 1•wd."long. may be slack.sc:::e ASTe1 esa05ernon s;- PLENUM The space above a suspended ceiling.
<br /> I scam i '•�.
<br /> 3 FA5TENMASTER s.ei.rmp
<br /> 1g°°°°minimgm— Light fixtures weighing more than 10 pounds and less than 56 lbs.Shall GRID The main beams and sass tees of the suspension system. REGISTERED
<br /> a coma SLACK WIRE A 12 gage wire that Is not tight or taut. aft
<br /> () I --_------- have tworuc 12 gage wiresattached may
<br /> be slat Comers Of the light fixture t0 HANGER WIRE 10 Or 12 gage soft.annealed Wlle Used a9 pri-
<br /> THRU-LDK 8"LAG 9p4ya.«lamic.ndnp Mm SPREADER or SPACER BAR A bar With notches f0
<br /> BOLTS AT EACH the structure above.These wires may be Slack. mery support for the grid system.Also called suspension wires. prevent the
<br /> • Suspension system from separating,also celled a stabilizer
<br /> GUARD P05i, Light Fixtures weighing more than 56 Ibs.shall be supported directly LATERAL FORCE BRACING The beating method used t0 prevent bar. LEN C.PAGE
<br /> INSTALL PER Ml from the structure above by approved hangers. calling uplift a restrict lateral movement during a seismic event.
<br /> Pendant mounted fixtures shall be directly supported from the structure Lateral force bracing consists ofverfical Sal dicular to the grid.d.Struts and splay wires. SPLAY WIRES grid.
<br /> installed at an angle rather then Darpan- STATE OF WASHMTON
<br /> above using li 9 gage wire or an approved alternatetsup support without MAIN BEAM The primary suspension member supported by
<br /> e, VERTICAL STRUTS The rigid vertical member used in later-
<br /> DOUBLE LVL EDGE using the ceiling suspension system for direct support.:--.. hanger rues,also known as the main runner,carrying tee,
<br /> STRINGER carrying at force bracing of the suspension system.Also known as
<br /> rryi g runner a mains. compression pasts,seismic pods,seismic struts.Common
<br /> .G Tandem fixtures may utilize common wires. MOLDINGICLOSURE ANGLE A light gauge metal angle or khan- materials are electrical conduit(EMT),metal studs or propri-
<br /> 3 2x 12 BLOCKING W nel fastened to the perimeter wall or partition to support the etary products.
<br /> 24'oc Mechanical Services
<br /> E Terminals or services weighing less than 20 lbs.shall be positively attached The Rwcs has bee,1—r T.I.DETAILS
<br /> 1"TREADS Ipamuy.0 gme co11ed,F,�ntlus,ry car overo ream.cis an,,,lasafto medl Wild. 11 th,d Deliboar and sA,the espnm,mewanandc�ning
<br /> to the ceiling suspension main runnersorto cross runners that have the p,omaeaeemna,ohe Hnda and th c,ad.thlco.1.dedoncal manes rot t1 muetlmenifiea wan Anacemng Nshd,y.A.me1k,111ttlagmcp1dO
<br /> samep In capacity a9 the main runners. ,..e Asrhn Eseo Secnon s+� amticopnln agency of FEmn.iha NWCB aew[he N1...ollentsh a.y)Iti aptom,.....anantl Meintent or NEHRP(Nationei EaMpuaka Heaertle Retivcgon
<br /> N✓D) 9 p ty Prognm)en agency FEMent i,Irai Emergency M.na9emams lot i),If la f—ly,er°eafaaetor,ecnmmentlaga Take-,
<br /> ak-intentletl ter enyapedfrr,,ty orgmion
<br /> Project.TM1ia technical dpcumenl is to acne as a puitleline antl it is not intentletl 1pr ,any.pldtic wnalrocllon prolett..NWCB makes no exprosa or implletl warranty or
<br /> INFILguars Chas of me bcnnlguea,con.vvct memoirs or mefedals Idehkl/e6 herein.
<br /> PAGE 3 OF 4 PAGE d OF 4
<br /> aF WRAP
<br /> GUARD WALL W/POSTSW/2%FRAINT DWO TR]c. Build to a Higher Standard. vvvawnw�b.org
<br /> "1TY OF°EUESRETT
<br /> WRAP GUARD WALL WI GWB.CAP yJ11H PLANTED WO TRIM.
<br /> FOR PERMIT
<br /> TYPICAL HALF WALL GUARDRAIL '7� SAT GRID A-8.0
<br /> Hs SCALE: 1" = 1'-0" v
<br /> SCALE: 1' = 1'-0"
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