Need a book? Engineering books recommendations...

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

Norbord "Windstorm" OSB panel

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Neil Moore alerted me to this by telephone--I have been 'archiving' SEAINT
digests to digest later, so some of the following comments may duplicate
those by others.

While I think it's great that this product is available in lengths intended
to span from the bottom of the sole plate to the top of the double plate,
that's about the only unusual thing about it.  And you can already get
plywood in lengths to 10 feet quite easily, OSB up to 12 feet.  Also, local
framing customs vary, so top-plate height may vary by 3/4 inch or more for
the same finished ceiling height.  But this is not the real issue.

The real issue (IMO) is that Norbord is misrepresenting this product.  I
would almost use the word "fraud", but will refrain from doing so in case
their attorneys are lurking....

Two quotes from their website:

1.    "A simple 2-step process in which Windstorm engineered wall sheathing
is simply nailed into place according to an engineer's specified nailing

Wow, how simple.  All you have to do is ignore a few laws of physics....

2.     "Ask your engineer what hardware can be eliminated in your houses to
meet code for your uplift and shear requirements using Windstorm."

Answer:  None that could not also be eliminated in a "regular" shear wall.

Norbord is marketing this as some great product that has passed tests by
NAHB and whoever else (glancing at a few other posts, these tests DID use
tie-downs...) and makes all those pesky threaded rods and tie-downs
unnecessary.  That is, unless some over-kill, way-too-conservative,
pocket-protector-clad, CYA obsessed engineer tells you that you still need
the hardware.

I see this in other industries--metal plate connected wood trusses, where
the contractor gets a quote for trusses, but then (if he's lucky) some
engineer comes along and makes him install several hundred lineal feet of
lateral bracing to keep the truss web members from buckling out of plane.
In the builder's mind, this over-kill, conservative, CYA requirement is the
_engineer's_ doing (we never had to do this before!) and has nothing to do
with the trusses themselves.

I'll sign off now before I get _too_ far into diatribe mode.

Thor Matteson, SE

******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at:
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*   Questions to seaint-ad(--nospam--at) 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: 
******* ****** ****** ****** ******* ****** ****** ********