Electrogalvanized inside exterior wall?

[ÉlPon]

Can you use electro-galvanized/zinc-plated inside external walls? Or is it considered as outdoor use? It's kind of in-between, not really on the warm side but not outdoors either...

I'm thinking for fastening a sill and some M20 threaded rods for a load-bearing steel post. Hot-dip galvanized doesn't seem to be available in regular stores, it's either electro-galvanized or stainless steel.

 

[hapazard]

If we disregard the cosmetic, surface treatment is hardly needed anywhere.

 

[ÉlPon]

So you mean the zinc-plated ones are sufficient in my case?
But you also say it's almost never needed. You mean the rust that forms outdoors is just on the surface?

 

[fribygg]

So you mean the galvanized ones are sufficient in my case?
But you also say it's almost never needed. Do you mean the rust that occurs outdoors is only on the surface?

The houses that were built 70 or 100 years ago had plain nails (untreated) and they haven't had any issues with that as far as I know.

 

[hapazard]

So you mean the zinc-plated ones are sufficient in my case?
But you also say it's almost never needed. Are you saying the rust that forms outdoors is only on the surface?

Very few situations where the fastener will fail before the material surrounding it, yes. Maybe underground or underwater. Screws might be a good idea to use a higher rust protection class outdoors since it can be difficult to remove them (if that's a concern).

As fribygg writes, everything was nailed untreated in the past and many 100-year-old facades are still standing.