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Can you differentiate trimmer joist as girders or beams?

Francis Vineyard

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How do you see deck framing floor opening around bay window cantilevers and chimneys?

2012 R507.2.2 Alternate deck ledger connections.

Deck ledger connections not conforming to Table R507.2 shall be designed in accordance with accepted engineering practice. Girders supporting deck joists shall not be supported on deck ledgers or band joists. Deck ledgers shall not be supported on stone or masonry veneer.

See the proposed 2015 deck code link below illustrates this model but there's seems to be ambiguity to have this designed per section R301 (R507.2)

http://www.nadra.org/contractor-code-guide/ICC_Committee_Proposal_2015.pdf

Francis
 
I interpret R507.2.2 "Girder" to be the supporting members identified as "Beam" in the figures.

The trimmers around openings are just "joists"

Perhaps the figure labels should match the Code text?

mj
 
: = : = :

Turn on the Bat [ Glenn's ] spot light and shine it up in to the clouds... :D

: = : = :
 
mjesse said:
I interpret R507.2.2 "Girder" to be the supporting members identified as "Beam" in the figures.The trimmers around openings are just "joists"

Perhaps the figure labels should match the Code text?

mj
Agree with you calling a beam a girder adds insult to injury!

Anyhow; Girder or Beam . . . floor joist are beams; header and trimmer joist framing of floor openings are collector beams i.e. girders.

Francis
 
I asked the same question in the AWC DCA6 workshop yesterday. I don't have a real issue with it, but ...........

R502.2.2.2 Alternate deck ledger connections. Deck ledger connections not conforming to Table R502.2.2.1 shall be designed in accordance with accepted engineering practice. Girders supporting deck joists shall not be supported on deck ledgers or band joists. Deck ledgers shall not be supported on stone or masonry veneer.

The trimmers do support deck joists or should I say they support the header that supports the joists. When I get a reply I'll post the answer.
 
Thanks Gary, I look forward to their answer.

Maybe I'm overthinking the terminology; similarly if the floor joist where parallel to the ledger; the edge "beams" are not prohibited to be supported but the center girder is by the ledger?

Francis
 
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well the 09 IRC states that a girder supporting deck joists cannot be supported by a ledger, and in my opinion that's what a trimmer does. I just asked Buddy Showalter (AWC) if the DCA was based on the 2009 IRC requirements how does their connection of a trimmer to the ledger (around a chimney) comply with the R502.2.2.2? I was told he would look into it since he didn't have his building code.

I'm lucky, Massachusetts adopted the Deck Guide as a part of our code under R301.1.1 so it says I can do it .....
 
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