Not Chinese Drywall, but what could it be?

This house was built in 2001 and one visible piece of drywall was labeled American Gypsum 10-10-2000. All the copper in the garage is dark black. The service panel ground wires, air handler refrigerant lines and coil. The air handler is only 6 years old. The copper on the water heater is not bad but it is only 3 years old. The copper pipes in the home are still bright and original. Any ideas please. I’m trying to word this in a report and CYA. Can car exhaust cause copper to turn this dark?

There was certain drywall manufactured in the United States that had the same characteristics as Chinese drywall, and it would found as early as 1999–2000.
Exhaust will not due that. Could be chemicals left in the garage. Did they have a pool? Or maybe fertilizer?

Thanks for ruling out the exhaust for me. The unit is vacant. It’s the middle unit of a three unit condo/triplex and the association maintains the yard and it doesn’t have a pool. I would assume it didn’t have pool chemicals or fertilizers. Thanks for the ideas.

Appears to show signs consistent with the presence of contaminated drywall.
Just because one piece was found to be "made in America " doesn’t mean that there is not contaminated drywall present.

Any chemicals stored near the panel, Such as weed killer or pool chlorine? Had that on a Home Inspection three months ago.

The drywall in different areas of the home could have come from different places. The air handler and water heater being replaced and showing these indications is cause for consideration. Possible that the garage drywall is contaminated while other drywall in the home is not.

Knowing your location would also be helpful, recommend adjusting your profile settings.

More details on this inspection and results please.:slight_smile:

I’m in Volusia Florida and this was in Palm Coast. I will adjust me settings.

Two things. First it is always a good idea to talk to the neighbors to see if they know of a problem.

Second a quick story. An inspector friend of mine drove to naples for an inspection. He had a similar situation. Only black pipe were in the garage and near the well system. We all thought it was sulfur in the water. His client had a company come in and do drywall testing and they found nothing. They were not satisfied and hired a company thtat had a drywall sniffing dog. The dog found two sheets of chinese drywall in the garage and no where else in the hosue. The inspector did not open every outlet. The outlet in the chinese drywall had the wires black. Interesting but scary stort.

High sulfur water can mimic Chinese drywall. If they don’t have a water system with an aerator it would be a good idea to get one. One other thing is the irrigation water being it’s not typically treated can find it’s way into the garage.

Murat ice acid pool or concrete floor prep for epoxy floor paint

Another possibility too.

I’ve had 3 houses like that this year.

2 in North Cape Coral.

1 in Lehigh Acres.

All 3 were 2006 houses.

Another company did their test and said sulfur.

All 3 were on a well.

One was really hard for me to believe that it wasn’t Chinese Drywall.
All outlet wires were black, copper fittings black under sinks, PEX fittings were black. The company still said sulfur.

From what I read, seems like the contaminated drywall also produces sulfur gases.

From the InterNACHI Flash Card project:

                 There has been quite a bit of discussion about this problem on inspection forums and although blackening of the pipes seems to be connected with the presence of Chinese drywall (which may not be marked as coming from China but possibly “México” or “Canada”), chemical fumes (often Sulpherous), possibly well water, possibly chemicals used to fumigate homes, and possibly having to do with the quality of the copper alloy, there appears to be no definitive answer.

You will not need to identify the source of discoloration. Some inspectors mention it in their reports, others don’t. Your client may ask about it. It typically does not cause deterioration of the copper.

Sample narrative from the InterNACHI Narrative Library:

Blackened pipes
Some copper water supply pipes had turned black. This is typically a reaction to chemical fumes of some type and may be influenced by the quality of the copper alloy. It seldom causes serious deterioration of the pipes. Accurate determination of the source of discoloration and the degree to which it represents a risk of deterioration to copper supply pipes or fittings lies beyond the scope of the General Home Inspection.

I pulled the panel cover off and all the copper wires on the breakers and ground bar were solid black. I found out that the prior homeowner stored weed killer and pool chlorine right next to the panel. Years of this has caused corrision. I recommend that a electrical contractor further evaluate the connections in the panel and replace the wiring if needed.

Corrosion or discoloration?

Perhaps it was Sheetrock made with flyash. Flyash has sulfur in it.

Good share, would you recommend further evaluation ? Or leave it at " lies beyond the scope of the General Home Inspection ".