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lrgure.^.
<br />Wteral lorce Bracing
<br />Lateral Force Bracing �rn����s z �„d 3�
<br />• Ceilings consiructed ot lath and plaster o� gypswn board, screw or nail aF
<br />tached lo suspended members thal support a ceiling on one level extending
<br />- " to wall shall be exempt from the lateral force bracing requirements.
<br />AIl�CI1C0 WBII moloing neyurtemmna
<br />�rgum � -
<br />Unallached Wall Molding i'.e�uirements
<br />.r.��ncs::��
<br />�ce bracing is the use ol verticxl struts (compression postsJ and
<br />�s (see ligure 2).
<br />7 areas exceeding 1,000 square teet, horizontal rest�ainl ot the ceil-
<br />strucWral system (la�eral force bracing) shall be provided.��.����; ��
<br />,mcu. ni ' 3.f� G.i.a c
<br />❑ee Bracing shall be 12 fee' on center (maximum) and begin no
<br />m 6 feet from walls. s-����<.,, cis,n s��-.�.-�:o��� 3-a
<br />play wires are to be four 12 gage wi�es attached to ihe main beam.
<br />arrayed 90° irom each mher and at an angle not exceeding 45° Irom
<br />oftheceiling y_��-�-cisc.�s-��:��,:����•,�.�
<br />�play wi�es shall be attached to the grid and lo the strucWre in such
<br />thal they can support a design load ol not less than 200 pounds or
<br />I desian load, with a safety laclor o1 2, whichever is greater (ligure
<br />., qscn,�,�,.,., �.n
<br />driven shol-in-anchors" (PAF's), when used tor seismic appliwtion
<br />' the prescriptive pa�h in Seismic Design Categories D, E and F, shall
<br />CGES appmval lor seismic applications and shall require "special
<br />n" i�respeclive ol lhe type of occupancy cale9ory the strucWre is in.
<br />iors for kicker wires (splayed wires inslalled tor purposes other than
<br />estralnt) are ezempt from �his requiremen�. �:.��.��.�. �i,�•. �� a.�,;;,,. 5���i,��,�
<br />es are to be within 2 inches ol the connedion of lhe vertical strut to
<br />:d ceiling. Eo rcc: uEca 5^�v=ic;u,es:i-�
<br />cing may be used in lieu of sptay wirea e����� •� ,:s:,e �^c;���� �_.� uz;� �.
<br />Nilh plenums less ihan 12 inches to structure a�e not required to
<br />ral lorce bracing. s�,�„�„� i��,�;i.����i u�,�u���� c�.�..,��"„��-:
<br />7ruls must be posilively atlached to ihe =uspension syslems and the
<br />d�OVe. c�,i��u. 2JSC:.3-t
<br />cal s�rut may be EMT conduit, metal studs or a prop�ietary compres-
<br />�, (see ligure 3).
<br />Cilfl j51�i�ures aa and Ab)
<br />dings (perime�er closure angles) are required lo have a horizontal
<br />inches wide. One end of the ceiling yrid shall 6e attached to the wall
<br />ni��
<br />.��� �y, ihe other end shall have a". inch clearance Irom the wall .�nd Iree to
<br />S�IdO. Sourc^� �SCE i-05 s^chon �05!,_ 2 b
<br />• Where substantiating documentation has been provided to lhe local jurisdic-
<br />tion, perimeter clips may be used lo satisly the requiremenis for �he 2•inch
<br />anglc.s�.,..,�,.s�:,i��,ac����„�, c.,i,m���a�n��.�o��.-.�;,�
<br />• The grid shall be attached at two adjacent walls (pop rivets or approved meth-
<br />od�. Sottits extending �o a point at leasl level wi�h the botiom plane of the giid
<br />and independently supported and lalerally braced to the strucWre above are
<br />, dcemed to he equivalent to walls. s.-,,.;•.. s,�; �. ���-�, .',.�^ �;�.: �,,°�°: ��.��`. _'-".^
<br />Spreader (spacer) bars shall be used to prevenl the ends of the main beams
<br />and cross tees at perimeler walls Irom spreading open during a seismic event.
<br />Perimetcr wires shall not be in licu ot spre�der bars. sn„�,-- �.:i�cn s; �-��, -;�--�-
<br />;_i
<br />• Sprcader bars are nol required al perimelers where runners are aflached
<br />directly to closure angles.
<br />• Wire tying is an acceptable alternative lo spreader bars.
<br />• Spreader bars are not required it a 90 degree intersecting cross or main is
<br />,. within B inches of the perimeter wall.
<br />• Where substantiating documentation has 6een provided to the local jurisdiction,
<br />perimeter clips may be used to satisty Il�e requirements for spreader bars. -
<br />.�,, i, c. ctate nt lle,�en. L'..�I.�ina::odrsUimsi;n
<br />:CP1N44251 WALL 6 GEILING HIIHiRU • SUS'LNV09 Sv5iCU5 �OP ACOUSiICr, l/��-14 GEILINGS
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