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This document has been revised based on current Building Code standards. In all buildings, other than structures classified
<br />as essential facilities,suspended ceilings installed in accordance with the prescriptive provisions of this document are
<br />deemed to comply with the current building reads interpretation.
<br />systems for acoustica
<br />l lay -in
<br />. - installation of suspension
<br />Hoed standards for theY_
<br />This document pro
<br />vides the IBA �.016refreY
<br />ceilings. Incorporation of this document will provide a more uniform standard for installation and inspection. This document is
<br />designed to accomplish the intent of the International Building Gode (IBC) with regard to the requirements for seismic design
<br />y p shall be
<br />engineering, the suspension system b Wn Hearin u
<br />items. Unless supported
<br />and related rteY
<br />category �, E and F for suspended ceilings .y g g, ,
<br />'
<br />installed per these requirements and those of the referenced documents. Manufacturers' recommendations should be followed
<br />where applicable.
<br />General Recommendations
<br />® Referenced sources per hierarchy: 2015 International Building Code (IBC), American Society of Civil Engineers
<br />g (ASCE ? 16); American
<br />Society
<br />of Testing Materials ASTM C 635, ASTM C 636, ASTM E 5800E 580M), and
<br />Ceilings and Interior Systems Construction Association (CISCA),
<br />• Partitions that are tied to the ceiling and all partitions greater than 6 ft in height shall be laterally braced to the
<br />structure. Bracing shall be independent of the ceiling splay bracing system. loans:; 6'E 746 Sec6on ;�3,581
<br />a. For further information on bracing of non -load bearing partitions, refer to NWCB Technical Document #200-501.
<br />• All main beams are to be Heavy Duty (HD)..
<br />• Ceilings less than or equal to 144 ft2 and surrounded by walls connected to the
<br />structure above are exempt from the seismic design requirements. oVrdeAaTA,f E580
<br />g
<br />Section 1.4
<br />These recommendations are intended for suspended ceilings and related
<br />components in areas that require resistance to the effects of earthquake motions.
<br />p
<br />Source. ASTM E580 e t r. 3,2
<br />All wire ties are to be three tight turns around themselves within three inches. Twelve -
<br />gauge aced 4 ft on center (Figure ure 1). sot«ce a„s;',JM c63t we r,on 2,3
<br />gauge hang p ( g
<br />Changes in ceiling planes will require positive bracing. Sdar:.afxT k Efii seta 5. 2 8_ Figure I
<br />=�1 ,
<br />NWCB
<br />HEADQUARTERS oREcr` N
<br />u r r !
<br />gu NU t .all i
<br />0-,
<br />O
<br />PAGE I OF 4
<br />Figure 2
<br />Lateral -Force Bracing
<br />Figure tr€ ure
<br />Maximum um ecommended Lengthsfor
<br />Vertical Struts
<br />Note Fary,ur a,,eesiyrvaretrha�? P Villrequire
<br />,IkufafiorZ.
<br />Figure 4a
<br />Attached Wall Molding Requirements
<br />Figure 4b
<br />Unattached Wall Molding Requirements
<br />i u ti w, H h, 120 n,aeii
<br />'A' any eWe,i
<br />Lateral -Force Bracing (Figures 2 and q)
<br />• Ceilings constructed of screw- or nail -attached gypsum board on
<br />one level that are surrounded by and connected to walls or soffits that
<br />are laterally braced to the structure above are exempt from seismic
<br />design requirements. Sowca,AScE. ,rsSxfion 2.5,8 1.S'M,5680S&,tieara 1.7
<br />• Ceiling areas of 1000 it" or less shall be exempt From lateral -force
<br />bracing requirements. a �rde:.srr et�ns
<br />a Lateral -force bracing is the use of vertical struts (compression
<br />posts) and splay wires (see Figure 2).
<br />• Lateral -force bracing shall be 12 ft on center (maximum) and begin
<br />no farther than 6 ft from ~walls. Boca=aerAuitt9E:i50Section 5.2.5.2
<br />• c splay wires are to be four 12-gauge wires attached to
<br />Seisms p y
<br />)
<br />� arrayed 9C° from each other and at an
<br />the morn beam. Wires
<br />angle not exceeding 450 from the plane of the ceiling. _surce.A3rM
<br />E550 Secrior, 5.5.8.2
<br />• Seismic splay wires shall be attached to the grid and to the
<br />structure in such a manner that they can support a minimum
<br />design load of 200 lb or the actual design load, with a safety factor
<br />of 2, whichever is greater (Figure 6b) rne: gfs,0_4zoae, 3-4
<br />m Power -actuated fasteners in concrete or steel shall not be used for
<br />sustained tension loads or for brace applications in Seismic resign
<br />Categories D, E, or F unless approved for seismic loading. Power -
<br />actuated fasteners in masonry are not permitted unless approved
<br />for seismic loading.
<br />Exceptions:
<br />1 Power -actuated fasteners in concrete, used for support of
<br />acoustical the or lay -in panel suspended ceiling applications
<br />and distributed systems where the service load an any
<br />individual fastener does not exceed 90 lb.
<br />2. Power -actuated fasteners in steel where the service load on
<br />any individual fastener does not exceed 250 Ib (1,112N). scum,&:
<br />• Splay wires are to be within 2 inches of the connection of the
<br />p Y
<br />vertical strut to suspended ceiling. Sowce,,ASTPKE 80 Sed;,bn528.2
<br />• Rigid bracing may be used in lieu of splay wires. Coerce. ASTM E560
<br />Section 5.2.8.4
<br />• Ceilings with plenums less than 12 inches to structure are not
<br />required to have lateral force bracing. , .ro;ffiien„3sarafi:v Depattremf
<br />• Vertical struts must be positively attached to the suspension
<br />systems and the structure above. S urn. 'tta,§5agr rs 5.2.E„2
<br />• The vertical strut may be EMT conduit, metal studs or a proprietary
<br />compression post (see Figure 3).
<br />Wall Moldings (Figures 4a and 4b)
<br />• Wall moldings (perimeter closure angles) are required to have a
<br />horizontal flange 2 inches wide. One end of the ceiling grid shall
<br />be attached to the wail molding, and the other end shall have a
<br />-'/4-in clearance from the wall and free to slide. Sourde: ASTw, E580 Seebn,
<br />S 2.2, Section 5..' 3
<br />• Where substantiating documentation has been provided to the
<br />local jurisdiction, perimeter clips may be used to satisfy the
<br />requirements for the 2-in closure angle. souroe: statq oforego,7, aoujtdinc
<br />r,odes D.,snsfoo
<br />PAGE w OF 4
<br />Fig;tre Sa fl Perimeter supporting clips shall be attached to the supporting closure
<br />angle or channel vvith a. minimum of two screws per clip and shall !-,e
<br />installed around the entire ceiling perimeter d e ,v: . sr 746
<br />The grid shall be attached at two adjacent walls (pop rivets or a p. F tied
<br />method), Soffits extending to a. point at least level with the bottom I iane,
<br />of the grid and independently supported and laterally braced to tt;r,
<br />structure above are deemed to be equivalent to walls, Soaf„. .;.<
<br />ASTAI j i i$ Yt I 4 i ,.._. .,,
<br />-. Spreader Bars (Figure 4b)
<br />Terminal ends of main runners and cross members shall be ties
<br />Figure jb Counter_;Io Irn;g together or have some other approved means to prevent their
<br />spreading. - ,fa, ..-
<br />n r runners are
<br />� required at perimete
<br />rs where
<br />e runns �
<br />Spre
<br />ader bars are not r ,
<br />C`
<br />r" Em l
<br />tl to closure
<br />re angles. direc
<br />M Spreader bars are not required if a 0' intersecting cross or main is
<br />within 3 inches of the perimeter wah.
<br />_ ... _._.. ..
<br />Where substantiating documentation has been provided to the l_fi,a
<br />jurisdiction, perimeter clips may be used to satisfy the regr_a[rennelitti for
<br />spreader bars. .t'ff
<br />Figure Pa
<br />danger(Suspension)Wir �Figurus-aand 5, Hanger and perimeter wires must be pliu mb within 1,6 unless (Figs,Irc 5r
<br />vertical hnnger wire att:aWhrnent counter sloping wires are provided (Figure5b)3,waqASTV o , >,
<br />nan-,� ,� _...___..., _, _, '111 Hanger wires shall be I2-gauge and spaced 4 ft on center.
<br />cdmno n€ir ` r,'w. Any connection device at the supporting construction shall be ca, able
<br />of carrying not less thiian 100 lb.
<br />s a , .._....._.._...._ ._ -..._. ..__ ..... Fasteners (PAFs) are an
<br />Powder Actuated Fa approved method of
<br />attachment for hanger wires, sovr�e A cs 74,,..
<br />Terminal ends of each main beam and cross tee must be support=;d
<br />Figure sr, within 3 inches of each wall with a perimeter wire or approved wail
<br />P i'p
<br />support (see Figures 4a & 5a).
<br />Spinved seisramir, aracim� wire attachment
<br />Wires shall not attach to or bend around interfering material or
<br />.�ni in t,.,,:. ,..€: ,,, equipment. Atrapeze or equivalent device shall be used where
<br />i p
<br />obstructions preclude direct suspension. Trapeze suspensions snail
<br />t,u to al ,. r ta_;_.
<br />be sized to resist the dead load and lateral farces approlarlat. ,._r, ", l
<br />seismic category. ry. _u
<br />.....m.. . Electrical Fixtures
<br />• Light fixtures weighing less than 10 lb shall have one 12-gauge hangs!
<br />wire connected from the fixture to the structure above. This wire rn av be
<br />slack,
<br />• Light fixtures weighing more than 10 lb and leas than 56 lb shall have l: v
<br />12-gauge wires attached at opposing corners of the light fixture to tin t
<br />structure above. These wires may be slack.AS rsl, E55"', ,
<br />s Light fixtures weighing more than 56 lb shall be supported directly ko n
<br />the structure alrxove by approved hangers.
<br />• Pendant -hung fixtures shall be directly supported from the ,structure v bove,
<br />using a 9-gauge wire or an approved alternate support without using thy,
<br />ceiling �i n sys for direct support.
<br />suspen�.rcn.�_ter�a,u dr pp
<br />Q
<br />Q
<br />AGi-a , ".
<br />Figure i
<br />°9 I
<br />Mechanical Services
<br />A to weighing than 0 lb shall b..
<br />wei hiin less to 2
<br />Terminals orservices c�
<br />positively attached to the ceiling suspension main runners
<br />i Y g p
<br />or to cross runners that have the same carrying capacity,
<br />as the main runners, 5.4.r
<br />• Terminals or services weighing 20 lb but not more than
<br />56 lb shall have; in addition to 5.4.1, two 12-gauge
<br />wires connecting them to the ceiling system hangers or
<br />the structure above. These ipiires may be slack Grrce_
<br />Xi
<br />a7"rirr 0 c) . erdora 5.4.2
<br />• Terminals or services weighing more than 56 lb shall be
<br />supported directly from the structure above by approved
<br />hangers.
<br />Seismic Separation Joints (Figure 7)
<br />All continuous ceiling areas exceeding 2500 ft- (232 m-),
<br />shall have a seismic separation joint, bulkhead braced
<br />to the structure or full -height partition that breaks the
<br />ceiling into areas of no more than 2500 ft'- (232 m2) and
<br />a ratio of the long to short dimension less than or equal
<br />to four. Each area shall be capable of allowing + or —
<br />14 in (19 mm) axial movement. Areas surrounded by
<br />Bulkheads or full height partitions shall be provided with
<br />closure angles. Each area with a seismic separation
<br />joint, bulkhe
<br />ad or f_ril-height ht
<br />partition shall hav
<br />e
<br />horizontal bracing or restraints. uo.,n.e. 4SCE 7-1639uf°or,
<br />Sprinklers
<br />For ceilings without rigid bracing; sprinkler head
<br />penetrations shall have a 2-in oversize ring; sleeve or
<br />adapter through the ceiling the to allow free movement of
<br />at least one inch in all horizontal directions. Flexible head
<br />design that can accommodate 1 inch free movement shall
<br />be permitted as an alternate, soo,r e: 5.2.8.5
<br />Glossaryfor this Document (regional terminology may ar )
<br />CROSS TEE The cross member that interlocks with the main
<br />NIOLDINGiCLOSU ANGLE A light -gauge metal angle or
<br />beams, also known as a cross runner or crass T-bar.
<br />channel fastened to the perimeter wall or partition to support
<br />the perimeter ends of an`accoustical ceiling grid.
<br />DIFFUSER A circular or rectangular metal grill used For the
<br />passage of air from a ducted system.
<br />PERIMETER Li A proprietary angle bracket attached
<br />directly to the wail molding/closure angle which allows for
<br />ESSENTIAL SERVICE UiL INC4 Any building designed to
<br />,X in movement in the Brent of seismic activity and interlocks
<br />be used by public agencies as a fire station, police station;
<br />properly with ends of grid system.
<br />emergency operations center, State Patrol office, sheriff's
<br />office, or emergency communication dispatch center.
<br />PEMNI ETER WIRE A hanger wrire placed within cn in of the
<br />surrounding walls.
<br />is The main beams and cross tees of the suspension
<br />system.
<br />PLENUM The space above a suspended ceiling.
<br />»� i as
<br />t12-gauge".SLACK
<br />HANGERo�ri�E 'i0. ©r soft annealed wire used.g
<br />B ` w re that is tightnot g or taut,
<br />..vurR f� 12r 'sU' e t
<br />9,
<br />primary support for the,gricl system: Also called a suspension
<br />SPREADER or SPACER BAR A bar with notches to prevent the
<br />wire.
<br />suspension system from separating, also called a stabilizer
<br />r.AT €4A�-PURGE BRACING The bracing method used to
<br />bar,
<br />prevent ceiling uplift or'restrict lateral movement during a
<br />SPLAY WINE Awire installed at an angle rather than
<br />seismic event, Lateral -force bracing consists of vertical struts
<br />perpendicular to the grid.
<br />and splay wires. i
<br />irERTiCAL STRUTThe rigid vertical member used in lateral -
<br />sa The primary suspension member supported by
<br />force bracingof the suspension system. Also known as
<br />p y.
<br />hanger or carrying tee
<br />han er wires, also known as the main runner y g ,
<br />g
<br />'
<br />-
<br />compression post; seismic pod or seismic strut. Commoncarrying
<br />runner or mains,
<br />electrical conduit EMT metal studs or
<br />materials are elect (- _ j,
<br />proprietary products.
<br />The MAICB ryas been servingthe conaructivn industry since '1960. It is recogni..aed as a
<br />technical authorio, educational body and spokesperson forthe vvaall and ceiling
<br />industry. it provides services to architect, andthe. construction community an all matterz,
<br />relating to the diversified wall and ce ing industry. As the industry's development
<br />and coordination orOranizat€on, the PJl<NCS saw the need to estabhsh this docur;nent to provide clad ication and the intent of NEHRP (National Earthquake Hazards Reduction
<br />Program) an ogencu of FENSA (Federal Ern,?rgency M,,, nagerncnt.Agem�yl. It is meant to
<br />serve a.. a set of recommendations and is not intended for any specific construction
<br />proyoct. € WGB rnakee no express or implied Warranty or guarantee of tile technigies, construction methods, or materials identif sd he in_
<br />PAGE 4 OF 4
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