Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Wall framing with I-Joists

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Plywood web joists are not, to my knowledge, intended to be used for axial loading in stud walls. With that said, I suppose it could be considered no different from building out a bearing plumbing wall where, instead of building  a double wall, two 2x studs are placed with their weak axis normal to the wall. The web would then act to brace the top and bottom chord/studs laterally. I think the issue is what has it been tested for?
I've used Parallam studs because the use of microlams posses a problem when nailing plywood as the spacing of nails becomes critical before the laminations will split. The best rule is to look at parallams and Microlams as beams or joists and checking the manufacturer's specifications for the size and maximum spacing of the nails which will limit the shear on the wall.
The other issue is that the PSL and LVL lumber is excellent for reducing a tall wall finish as they have little or no cupping of the studs. The downside is that they are hard as hell to nail - especially PSL lumber. I think the savings in labor and materials for the use of PSL studs in designs that require tall walls such as a church santuary, the PSL is worth the cost as it will save in material scrap and in labor that may be required with conventional stud walls to shim the walls where the eye can see the crown of the studs to get the gypsum finish with the least amount of billible hours.

Check with your I-Joist supplier for any test data for the use of plywood web joists as possible use in stud walls. You may find that building a double wall is easier.
 
Dennis S. Wish, PE
California Professional Engineer
Structural Engineering Consultant


----- Original Message ----
From: Joseph R. Grill <jrgrill(--nospam--at)cableone.net>
To: seaint(--nospam--at)seaint.org
Sent: Thursday, October 9, 2008 9:22:36 AM
Subject: RE: Wall framing with I-Joists

You should check with the I-joist mfg.  I don't believe that they are to be
used in an axial compression situation.
Joe Grill

-----Original Message-----
From: Lloyd Pack [mailto:packman90(--nospam--at)qwest.net]
Sent: Wednesday, October 08, 2008 11:27 PM
To: seaint(--nospam--at)seaint.org
Subject: Re: Wall framing with I-Joists

Yi,

It would seem to me that the I-joists would not work well for bearing walls.
They would work okay at gable end walls, though.  You might consider
Microllams (LVLs) for the bearing walls.  They come in the same depth
as the I-joists and will have better axial strength.  Trus-Joist might even
make a less expensive stud grade material that has greater depth than
typical studs that might work less expensively than LVLs.

Take Care,
Lloyd

On 7 Oct 2008 at 12:07, Yi Yang wrote:

>
> List,
>
> I have a residential project in CA, where the architect is considering
> using 12" nominal I-joists for wall framing, to provide additional
> insulation space, and to create a thick wall.
>
> Usually, to get the thick walls, the walls are double framed. I have
> not seen or worked on a project that uses I-Joist in wall framing. I
> talked to TrusJoist, and they told me that we are on our own if we are
> to use them for walls. The architect told me that this system is used
> in Europe, and some in Canada.
>
> I'm wondering if there is a whole industry out there that supports
> this kind of construction, that I'm completely unaware of (providing
> connectors, blocking system etc.). The I-joists are not designed for
> large axial compression. I imagine we would have web blocking in many
> places, and it would just cost too much to build.
>
> I appreciate any input and suggestion on this.
>
> Thank you very much.
>
>
>
> YI YANG, S.E.
>
> Do you really need to print this e-mail?
>


******* ****** ******* ******** ******* ******* ******* ***
*  Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
*  This email was sent to you via Structural Engineers
*  Association of Southern California (SEAOSC) server. To
*  subscribe (no fee) or UnSubscribe, please go to:
*
http://www.seaint.org/sealist1.asp
*
*  Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you
*  send to the list is public domain and may be re-posted
*  without your permission. Make sure you visit our web
*  site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********


******* ****** ******* ******** ******* ******* ******* ***
*  Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
*  This email was sent to you via Structural Engineers
*  Association of Southern California (SEAOSC) server. To
*  subscribe (no fee) or UnSubscribe, please go to:
*
http://www.seaint.org/sealist1.asp
*
*  Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you
*  send to the list is public domain and may be re-posted
*  without your permission. Make sure you visit our web
*  site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********