Caution... simpson tie product and pressure treated wood...

[NM_Shooter]

Just got off the phone with Simpson Tie tech support.  I was asking to find out if older ST products hold up well against corrosion with new pressure treated wood.  What I was told spooked me a bit.

The tech that I spoke with told me that most of the stuff for sale at home centers (HD, Lowes), was was coated with their standard G90 Zinc coating.  That coating only provides a low level of corrosion resistance. 

If you look in their catalog, around pages 10/11, it shows tables for corrosion resistance. 

I had hoped that their product was a hot dipped Galvanized coating, but it is not. 

Looks like my beams will be made out of non-PT wood.  Doggone.

-f-

[MikeT]

As I recall, they have a Z max coating which offers a level of protection which is better than normal but not as good as stainless steel.  That is what I have been purchasing.

mt

[Don_P]

The Zmax connectors are labelled as such and have twice the galvy of the old standard ones. They are the only connectors stocked in the stores here although the transition period a few years ago was pretty rocky. All fasteners need to be at a minimum HDG, hot dipped galvanized as well. Do not mix galvy and stainless. Our flashing material is still all over the road, copper is always safe with the ACQ as that is what's causing the galvanic reaction, they bumped up the copper content to replace some of the qualities they got from the chromium and arsenic in the old CCA treated lumber. Do not use aluminum in contact with ACQ, it will eat it before you finish nailing it. Check any fasteners going into things like sills. I typically now frame the floor and sheath with 2 guns, one loaded with ACQ compatible nails and the other with uncoated nails. Otherwise I shoot the more expensive nails the whole way thru which eats up a fair amount of money.

[Redoverfarm]

Easy fix Frank. If you have the room just slip a piece of #15 or #30 felt between the two. That will limit the passage of the chemicals from on to the other.  I learned this when I used a termite shield under my bottom plate.

[MountainDon]

Most, but not all, connectors sold at the local HD and Lowe's are now Z-Max, denoted by a 'Z' suffix. Lowe's Rio Rancho even has the H-1 in Z-Max as well as LSU series joist hangers and many post/beam connectors.