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Borate-treated foundation sills instead of Stainless Steel

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I believe I posted something to this effect in the past, but it bears
repeating.

Borate-treated wood does not corrode fasteners to the degree that other
treatments do.  Borates are perfectly acceptable for foundation sills
("mudsills").  The other treatments (ACQ, CC, ACZA, CA) may attack wood even
more aggressively than the Simpson tests indicate.  A forum for contractors
had a post describing anchor bolts that had corroded significantly before
the house was even finished.

I expect a feeding frenzy of class-action and other lawsuits over fastener
corrosion in the near future.  As soon as mold has been milked for all it
can be--only fastener corrosion, IMO, is a REAL problem as compared to some
black stains concealed in your walls (yes, when the black stuff starts
spreading into the living spaces, I would consider that a problem....)

Beginning two years ago we began placing the following warning on all our
foundation plans:

===========================================
Warning !

As of January 1, 2004, wood preservative manufacturers switched to chemicals
intended to cause less harm to humans than those used in the past.  Some of
these new chemicals tend to corrode metal fasteners much more aggressively
than the preservatives used in the past.

Type  316 STAINLESS STEEL is required for all anchor bolts, washers, screws,
lags, nails, sheet metal clips and any other connectors in contact with wood
treated with ACZA, ACQ, CA, or CC.  This includes fasteners driven through
shear panels and other sheathing or cladding materials and into the
pressure-treated stock, nails securing studs to mudsills, and clips and
nails fastening rim joists to mudsills.  Hot-dipped galvanized fasteners and
triple-galvanized ("Z-Max") clips are not adequate.
The Maze Nail Company manufactures collated stainless steel (gun) nails;
phone 800/435-5949,  www.mazenails.com

To avoid the requirement for stainless steel fasteners, use wood
pressure-treated with Disodium Octaborate Tetrahydrate (DOT) or Sodium
Octa-Borate (SBX) where preservative-treated wood is needed.  Wood treated
with borates is not toxic to humans and animals, is less corrosive than the
"old" type of preservative, and is allowed for use where it will be
permanently protected from liquid water, such as for foundation ("mud")
sills.  (Borates are not waterproof, and may not be used where exposed to
ground, weather or rain-splash, such as for fence-posts or outdoor deck
framing.)  Two acceptable borate treatments are the Calbor or SillBor
brands.  Borate-treated wood is available from BMC West outlets.
=============================================

GO,  BORATES ! ! ! !

Thor

www.shearwalls.com


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