Don't use these nails on treated wood?

scarrell

I am buying a framing nailer and have been looking at nails. The one's that come on the plastic strip say in fine print "Do not use on treated wood". Anybody know why? Thanks.

bob the builder

Because the treated will eat away at the fastener. You need to purchase nails that are a.c.q. appropriate. Stainless steel, copper, hot dipgalvinized. The cost about twice the price...

Bob

scarrell

Thank you very much

mighty anvil

Over a year ago the wood pressure treating industry voluntarily changed their treatment chemicals to avoid the growing controversy about arsenic being harmful to humans. Wood using the old formula is by now all gone and so the p-t wood sold now has the lower arsenic, higher copper content. The old material was never banned so if you run across it there is no reason not to use it if you aren't worried about arsenic. The new copper content will corrode steel and even zinc coated steel unless the coating is heavy enough. The corrosion potential of the new formula is estimated to be 2.5 to 4 times greater than the old stuff.

Nail and connector manufacturers have upgraded their zinc coatings (hot-dipped galvanizing) and have added labels about performance with p-t wood. Of course, stainless steel is the best. Copper obviously is not strong enough for use except as flashing. Never allow aluminum to be in contact with or directly below p-t wood since it is the least noble of construction metals. Exposed aluminum only survives on buildings because it forms a thin patina from exposure to the air and then virtually stops corroding. In the presence of more noble metals and moisture it will rapidly be consumed by corrosion as if it had evaporated. The inappropriate placement of aluminum flashing is one of the most common mistakes builders make.

WR Grace now makes a material (Vycor deck-protector) that can be wrapped around p-t wood to reduce the problem.

http://www.graceathome.com/pages/dec..._corrosion.htm