Dating corrosion of metal lath

[PSUengineer1]

Is anyone aware of published research used to date water damage to metal lath (rust)? I have rusted lath near a plumbing leak. The lath is orange in its discoloration, with rust bleeding onto the remains of the plaster ceiling. I need to determine the age of the corrosion; specifically if the corrosion is 14 days old or less.

I don’t know an exact source that provides a duration, specifically for metal lath. I do know that corrosion of steel is dependent on several factors, such as atmospheric conditions, exposure to moisture, exposure to chemicals, type of steel (mild steel A36, A992 etc..), zinc content, and steel thickness, to name a few that may be most relevant for metal lathe in a stucco.

Thank you for your consideration.

 

[TehMightyEngineer]

In my experience corrosion rates are +/- months (if not years). Some start slow and accelerate, some are constant, others will flash rust and then stop corrosion. There are far too many variables to establish a reasonable estimate of days.

However, the best approach would be an on-site experiment using the identical metal and environment. That would eliminate almost all the variables and control the rest. Should establish at least an approximate corrosion rate with +/- days accuracy.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[JedClampett]

I once tried dating corrosion of metal lath, but preferred girls.

 

[John2025]

Prude

 

[SkipVought]

So with dating girls, do you take a cross section, or is there a non destructive method that you prefer?

Skip,

_{Just traded in my OLD subtlety...
for a NUance!}

 

[jayrod12]

It's more like a testing program, you play a game called just the tip.

 

[Ron]

PSU...no way to accurately do this; however, if stains are showing, it did not likely happen in the last 14 days. Usually takes quite a bit longer.