Yikes.  Now that I have that right at least now my attic won't sag into my
kitchen!  Have we all run those equations on our airplanes now??

BTW, a 2 X 12 is 1.5 X 11.5.  I'll actually be making flitched beams by
sistering 1/4" by 6 steel plate to the existing 1-3/4 X 5-1/2" attic joists
and then furring them to even out the ceiling, but I'm analyzing the steel
size to make sure it can carry the weight alone (E for steel = 30,000,000).
 The existing wood will then exist for nailing alone.

Now then, for floors, deflection s/b < 1/360 of the span  of 144 in in this
case, .4"  The load @ 60lbs/lineal ft = 720 lbs, soooo

if deflection = (5(weight, evenly dist'd)(span in inches^3))/(((384
E)((beam width )(beam height^3))/12))

then I should get .21", which is well within acceptable limits.

Did I screw any of this up? I gotta try this w/5" plate, maybe that will
work.  Did I mention there isn't much going on at work today??

Have a great holiday!

Tom

Tom Jelly, HSBC Futures at the CME  312-559-1057 7am-2pm.   773-348-6549
(H)  773-206-6764 (cell)

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