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# Re: WOOD - Load bearing studs in a party wall

• To: seaoc(--nospam--at)seaoc.org
• Subject: Re: WOOD - Load bearing studs in a party wall
• Date: Thu, 23 Oct 1997 00:54:03 -0700

```The 94 UBC at sect. 2306.8, in its last paragraph, appears to squarely
least one side."
The depth, not breadth, is used in calculating le/d.  Maybe it's that way in
later versions too. The same paragraph also covers truss top chords having
planks or sheathing nailed to them on one edge; same outcome. See 2306.7 for
the stud's flexural role: for 2:1 ratio as for 2x4's, no lateral support is
required. CG.

At 03:54 PM 10/22/97 -0700, you wrote:
>I am checking the load bearing capacity of a wood framed wall that is
>intended to be used in a party wall. This party wall consists of 2x4 studs @
>16" mounted on 2x6 top and bottom plates. These studs exist on each side of
>the wall. In other words, there are 2x4 studs @ 16" framed flush to one edge
>of the sill plate and 2x4 studs @ 16" framed flush with the other edge of
>the sill plate. These two "rows" of studs are offset so that there actually
>exists 2x4 studs @ 8".
>
>In a "normal" wall, these studs are laterally braced on both faces. For an
>interior wall, there is gypsum wallboard on both sides. For exterior walls,
>there is some kind of exterior sheathing (plywood or stucco) with gypsum
>wallboard on the interior. Therefore, these studs are laterally braced
>continuously about the minor axis. To determine the axial capacity based on
>l/d ratios, I have used the distance between the sill plate and top plate
>for my "l" and the depth of the stud for my "d".
>
>In this party wall case, there is gypsum wallboard on only one face of the
>studs. True, it is the compression face for the Code mandated 5 psf
>partition load, but one edge is still laterally unsupported. My gut feeling
>is that the capacity of the stud is somewhat less than if there was gypsum
>wallboard on both faces but a lot more than if there was no gypsum wallboard
>at all.
>
>Since I realize that I'm not the first structural engineer to be asked to
>use a party wall as a load bearing wall, I am curious what others have done
>in the past to determine the capacity of studs laterally braced on one face
>only.
>
>Regards,
>Bill Allen

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