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RE: galvanized vs electroplate

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It's worth noting the 2009 IBC (and 2009 IRC) do in fact differentiate (to some extent) between PPT and FRTW. The FRT manufacturers pushed for the split during the interim cycle and it carried through to the final codes.

Basically, for FRT in interior dry applications, you'll now be directed to the manufacturer recommendations. So if they say their standard coating (like the G90) or plain steel fastener is OK, you'll be good to go.

Also, the 2009 IBC will carry an exception for using plain steel fasteners with borates in interior dry applications.

On the electroplated versus HDG I'm not sure I have much advice. I know there has been substantial debate in the code arena among the various fastener manufacturers and coating reps on the quality of mechanical versus HD galvanizing, and attempts to allow more mechanical galvanizing have failed. I vaguely recall some discussion of electroplating somewhere along the line but I can't remember the context at the moment.

Gary

Gary J. Ehrlich, PE 
Program Manager, Structural Codes & Standards 
National Association of Home Builders (NAHB) 
1201 15th Street, NW, Washington, DC 20005 
ph: 202-266-8545  or 800-368-5242 x8545 
fax: 202-266-8369 
gehrlich(--nospam--at)nahb.com 
Attend the 2010 International Builders' Show 
January 19-22, 2010, Las Vegas, NV 
www.buildersshow.com
www.builderbooks.com
www.housingeconomics.com

-----Original Message-----
From: Thor Matteson [mailto:thorm(--nospam--at)sti.net] 
Sent: Thursday, June 04, 2009 11:18 AM
To: seaint(--nospam--at)seaint.org
Subject: RE: galvanized vs electroplate

I'm on digest mode, so forgive me if this has already been answered....

You probably are referring to IBC/CBC section 2304.9.5, which does not 
discriminate between the many different kinds of chemicals used for 
preservative or fire-retardant treating.

Don'tcha love the building code?  Some treating chemicals (borates) are 
almost completely benign, and some others (ACQ, ACZA) will eat through 
foundation bolts in a matter of months, according to observations by 
contractors.  Yet the code lumps them all into the same category.  Remind me 
not to buy a house built after 2004, when the new, higher-copper-content 
treatments came into widespread use.  More info at 
www.shearwalls.com/treated_wood.html

My recommendation:  Use borate-treated wood for mudsills and anything else 
that will be protected from water or rain-splash.  Borates do not corrode 
fasteners and they don't harm mammals (in case you want to use mammals to 
hold your structure together ;-)

There's also the exception to Section 2304.9.5 that allows anything BESIDES 
nails, timber rivets, screws and lags to be mechanically galvanized.   I 
assume that this permits bolts, all-thread, and apparantly 
hangers/clips/straps/tie-downs etc. to be mechanically galvanized instead of 
HDG (note that electroplated is NOT the same as mechanically galvanized). 
But from the reports I hear from contractors in the field, I would only 
recommend HDG unless using borate-treated wood, and Stainless Steel for the 
more aggressive chemicals.  Simpson's website and catalog also have some 
good information and recommendations.

Good luck--

Thor Matteson, SE
www.shearwalls.com



> From: PFFEI(--nospam--at)aol.com
> Subject: galvanized vs electroplate
>
> the building code specifically requires hot dip galvanized wherever metal
> is in contact with pressure treated framing.  city of LA plan includes 
> this
> in plan check correction sheets and requires it to be written onto  plans.
> in practical application, suppliers do not seem to be changing  stock to
> hot dip galvanized for rods and hangers (hot dip galvanized nails seem  to 
> be
> readily available).  we have contacted a couple of suppliers  and they do
> not stocking hot dip galvanized rods and Simpson hangers  in hot dip
> galvanized are a special order.
>
> i am curious how others are handling this issue.  is electroplated  steel
> (readily available) sufficient for rods and is the standard Simpson 
> coating
> (galvanized G90) adequate for hangers?
>
> thank you for your comments.
>
> sincerely,
>
> paul franceschi, s.e.


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