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How to prevent wood rot caused by galvanized bolts in pressure treated wood?

It has been suggested to me that the severe black wood rot I have experienced around the galvanized bolts in the (anti-termite)(green) pressure treated lumber is due to the galvanic reaction between the galvanized bolts and the copper arsenic salts, etc. in the pressure treated wood. This has probably been exacerbated by our warm moist climate in a wet area of Hawaii, not to mention this was immediately below a hot tub and a redwood deck that probably provided some tannic acid ⇦this on eBay or Amazon [affil links] in the run off as an electrolyte.

 

In rebuilding, how can I prevent the same problem? Most of the framing is pre-existing pressure treated wood, and I cannot afford stainless 1/2 X 8 inch bolts. I am considering painting the hot dipped galvanized bolts and have read the AGA "Duplex Systems: Painting over HDG" but sometimes too much information is as confusing as not enough. Is painting the answer? Is there a simple spray or dip I can use as a homeowner? Should I dip the final result in toilet bowl seal wax before inserting the bolts in the wood? Thank you for any help you can give me.

David Pursel
Consumer (homeowner) - Honolulu, Hawaii
2005

HDG got along fine with the old copper-chromium-arsenic pressure treatment. It does not get along as well with the new fangled pressure treated wood. Some lumberyards sell fasteners with a special coating for compatibility with the new stuff.

James Watts
- Navarre, Florida
2005

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2005

Now that the pictures have been included, I seriously doubt if the fastener is in any way the cause. Pressure treatment for wood does not go all the way into the wood, so the inside has less resistance than the outside does.
I think that your problem is water. Aiding and abetting the problem is cracked wood.
Solution probably is to seal the wood with two or three coats of seal and another coat every year or so, depending on the amount of water than is gets and the amount of use.
I very seriously doubt that stainless steel fasteners would slow down the rot. It would look better because there would be little rust.

James Watts
- Navarre, Florida