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RE: galvanized vs electroplate

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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

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

From: PFFEI(--nospam--at)
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.


paul franceschi, s.e.

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