# Identifying load bearing walls in 2 story home. . .



## Alan (Apr 12, 2006)

The house in question is a 1965'er, post and beam type foundation with 2 x 6 T&G subfloor. 

Now-a-days when we build houses and need to support walls, we need footings and pony-walls below the bearing walls, correct? How do I determine 1st floor walls that are bearing loads from the 2nd floor in a post & beam foundation? Are they only the exteriors?

Thanks in advance,

-Alan


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## oh'mike (Sep 18, 2009)

The floor structure of the second floor usually needs to sit on a load bearing wall---typically the center wall---how wide is the house ? which way do the second floor-floor joists run?

(and nice to see you again!)---Mike---


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## nap (Dec 4, 2007)

> How do I determine 1st floor walls that are bearing loads from the 2nd floor in a post & beam foundation? Are they only the exteriors?


there are no bearing walls, including the perimeter walls in a post and beam construction. The posts and beams are the supporting structure. The walls are simply filler.

hey, ignore that. I read foundation and thought building for some reason.

so, after that embarrassing answer. I'll try again.

as Mike was alluding to, typically a load bearing wall is going to run perpendicular to the 2nd story floor joists. Head to the crawl space, look for support posts within the perimeter and a beam running perpendicular to the floor joists. It would be a safe bet that any wall directly above such a beam is going to be load bearing. 

If there is no support under the first floor to support a wall above, it takes some review of the design to determine if any given wall is load bearing. Obviously if not directly supported by foundation, the load capacity would be diminished but that doesn't preclude it from being load bearing entirely.


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## Alan (Apr 12, 2006)

oh'mike said:


> The floor structure of the second floor usually needs to sit on a load bearing wall---typically the center wall---how wide is the house ? which way do the second floor-floor joists run?
> 
> (and nice to see you again!)---Mike---


There is a wall in the house that runs approximately center, but only about halfway down the length of the house. The beams are running longways, and one would assume that the 2nd story joists would run the shortest span possible. I'm going to say ~25 feet could be 23 or 24, but I don't know the size of the second story floor joists without doing some exploration. Not ready for that yet anyway, since the house aint ours yet. :laughing::thumbup:

I can give myself a rough measurement on that center beam and see if it is carrying the center wall. . . . My bet is yes, but then i'm curious the section of the house without the 'center wall', what's holding that baby up? The joists would have to run ~ 14 feet unsupported in order to make that span. Maybe they change directions?


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## oh'mike (Sep 18, 2009)

More likely the "unsupported" section is supported by a beam at the same height as the floor joists--

---floor joist hangered off the beam---decks are often constructed like this when there is not enough ground clearance for the girder to sit below the joists.


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## Gary in WA (Mar 11, 2009)

Scroll down a page; http://books.google.com/books?id=Qb...EwAQ#v=onepage&q=post and beam floors&f=false

A Doug fir/Larch #2, 16”o.c. will span 14’ for bedrooms above; http://publicecodes.citation.com/icod/irc/2009/icod_irc_2009_5_sec002_par017.htm?bu2=undefined

Gary


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## Alan (Apr 12, 2006)

Thanks for the info guys. I'll have some exploring to do when we get in there I suppose.


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## Alan (Apr 12, 2006)

GBR in WA said:


> Scroll down a page; http://books.google.com/books?id=Qb...EwAQ#v=onepage&q=post and beam floors&f=false
> 
> A Doug fir/Larch #2, 16”o.c. will span 14’ for bedrooms above; http://publicecodes.citation.com/icod/irc/2009/icod_irc_2009_5_sec002_par017.htm?bu2=undefined
> 
> Gary


I see above if bumped up to 12" O.C. a 2x12 will go 23'. Maybe that is what they did, and 2x12 throughout. Again, exploration needed, but thanks for the info.    :thumbup:


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