by Jerry Peck - Codeman on Thu Feb 19, 2009 11:59 am
Hi In South Florida,
First, how can you tell if the drywall is Chinese drywall? Possibly by removing a large enough piece that you can see the name on the backside along the factory edge, the manufacturer, Knauf, or Knauf Plasterboard Tianjin Co. Ltd. of China, which is a subsidiary of Germany-based manufacturer Knauf.
Second, in another question from yesterday, see where I have posted an answer to it, the entire electrical system needs to be inspected for damage and potential replacement.
Additionally, from your description, here are some other things which need to be inspected for damage, or simply replaced outright.
You mentioned there was copper plumbing piping and which the owners have experienced a few leaks already, thus, even with out the previous leaks, but especially with those previous leaks, the copper plumbing piping is susceptible to the same damage as the copper in the air conditioning coils which everyone is having a problem with. When the Chinese drywall is removed, the copper piping should be inspected for any signs of any affects from whatever the Chinese drywall is out-gassing, the plumbing system piping should also be pressure tested to 160 psi - twice the 80 psi pressure the system is allowed to operate at. However, if there is any question as to the suitability of the copper plumbing piping for continued use, it should be replaced as replacement with all of the drywall removed is less costly than even just a few more repairs down the road as the copper continues to fail, and may eventually lead to having to replace the copper piping, which means removing the drywall again.
Another item which would need to be inspected would be the metal studs commonly used in construction in South Florida (and other places around the country - some areas still build mostly with wood framing) as whatever is out-gassing from the Chinese drywall and is eating through copper could certainly also be deteriorating and corroding through the protective galvanized coating of metal framing, its screws, all steel and other metal fasteners of every type (nails, screws, large bolts and nuts, anchor pins into concrete, etc.
The more I think about what could potentially be affected by the effect of whatever is out-gassing from the Chinese drywall, the list of items almost becomes all inclusive, truss plates for metal plate connected trusses for instance, with the exception of wood and plastic, that could be a very long and intensive list of items used in the constructing of a structure or building.
Codeman
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired