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� - . � � r'`�;:D D�C4:S - SA(�1PLE CALCULATIO��S FOR USIt�G THE SPA� iABLE • a — I C�se I Solu�ion: ReTer to table for jcist and beam sizes . �� Example: a = 12' , Post 5pacing = fi' P.efer to tne span table. Joist size may be eiti�er. 2x8' s 12" O.C. or 2x10's I6" O.C. Beam size may be either 3-2x8'x or � 2-2x10's. �dSe I1 Solution: Use ."a" �01' �01Si. S1:G d(ld ��d�� T ��b�� �0 i � b deternine beam size (Tne length or "b" is restric�� by � 4 �� .�j botn the length of "a" and the size o� �he joists) . I � � cx�:-�ple: a = 8' > b = Z' , Post Spacing = 10' , rind the jaist size required by looking under 8 ' on the I table. Joist ler.ath is indicated as 2x6' s i6" O.C. or � Zx8 's 24" O.C. For sizing tne bear, use a joist ieng�h o; ; 10' (8' � 2' = 10' ) and a pos� spacing o� 10' . The ta bie . indicates that 4-2x8 ' s or 3-2x10' s are required �or the b�am. Case III Solution: Use "a" or "b" , whichever is areater, to deterr,�ine jois� S1Z2. ��SE ��d° -r '��FJ�� 0 dete�ine tfl� S1ZE �� Be�� No, 1 ard use joi;t 1 ergt�� "b" to det2r;ri ne the _ a � � , size o� Beam_t�o. 2. - • � f �---�--� r - � �xample: a - 6' , b - 7 ' , Pos� Spacing 9 ' ! .� � ihe joist length (7 ' ) is d2te �„ined by �he longest span jois� f ("b") . The tzble indicates t'r�at 2x5's 1b" O.C, or 2xo ' s 24" O.C. zre required ror a 7 ' sp�n. For Be�� No, i , use �oist ieneih 3��:.� i REGn ? o� 13 ' (6` + 7 ' = l� ' ) ard pos� spacing cfi 9' . The tabla � ; indicates that 3-2x10' s cr 2-2x1?'s are reGuired for 5eam ��o. 1 . For Bea�n Ho. 2 use joist length of 7 ' w��h a �post spaE�ng of 9 ' . The table indicates that 4-2x6's or 3-?x 8's are required for Beam ho. 2. -- • �aSe TV 5olution: Use °Z�� 01" ��b�� , W(11Ch?Ve'" 1S greater , t0 de=ernine jO15t SiZ2. �S� ��d�� T ��b`� t0 �Etef�^+,1i12 t�e S1Z� OT Beam K0. � d�Q ��G�� T ��C�� t0 determine t��lE S1Z° Or aEZ[il rv0. 2. � (Tne lengtE� of "c" i s ?"25�t"7C�� by bct7 the 1 ergth or "b" and the size of the joist) . � �a _J , b ► c �� txample: a = 7 ' , b = 8 ' , c = %` , Post Spacir.g = 12 ' � , �— - The longest joist span is 2 ' ; �hererore, the table indicates that 2x6's 16" O.C. or 2x8's 24" O.C. are required. For r1o. 1 No. 2 Beam Ho. 1 , use joist lergth o� 15' (i ' + 8 ' = 15 ' ) and ;seam Beam post spacing o` 12 ' . The table indicates that 3-2x12 ' s are required for Eeam ho. l . ror 3eam t1o. 2, use joist length of . � 10' (8' � 2' = 10' ) and post spacing of 12' . The table . irdicates that 3-2x10's cr 3-Zx12's ar.e required, for _ Beam Ho. 2. � N07ES: Post size must be adequate to provide full beam bearing , ie. , -one-member� a nd two-member beams r�ust be placed on a 4x4 post, three-member beams must be placed on 4x6 o r bx6 posts, and four-me+�ber beams must be placed on 8x8 posts. Most of the boxes in this tabl�e contain two optional means of .support. Wood_. members may be increased above those indicated in the table, bu� in no event may lesser m�nbers be used.