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[SEAOC] UBC Sec3102.6

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     I would like to know what others are doing to comply with the "94
Uniform Building Code  Sec 3102.6 on wood chimneys for  metal pre-fab
fireplaces in houses. This is typically a sheet metal round flue inside 2x
wood frame rectangular chimney which is typically stuccoed or  brick veneered
     This is new to the ('94) code. In the past i have been using simpson  cs
straps but they are not 1/8" thick ( 11 gauge ). It would appear only Simpson
mst60 or 72 are thick enough but they will not " loop  around " well.  Also ,
the code is not clear about how far into the roof or floor to extend the
straps. I have been going 6'. I assume the code is refering to looping around
the outside of the wood chimney, not the metal flue inside. Also it would
only make sense to apply to exterior not interior chimneys ( different
problem there ).
     In looking at tracts around town here it appears no one is complying
with this section at all. This did seem to be a problem i saw when providing
earthquake damage reports after the Northridge earthquake, especially when
the chimneys were tall as with steep pitch roofs or a nearby 2nd story.
     I would value your opinion on this subject. I may be misunderstanding
this section.

Tom Harris, SE
Thousand Oaks, CA

94 UBC Sec 3102.6  2nd Para, page 1-375 of vol 1 :

    Metal chimneys shall be anchored at each floor and roof with two 1 1/2-
inch by 1/8 inch metal straps looped around the outside of the chimney
installation and nailed with not less than six 8d nails per strap at each