Badly Corroded and rusted metal roof components:

[Thomas McKay]

Inspected 2005 block home on a slab in central Florida and found excessive corrosion during attic inspection to all metal roof components to include shiners, roof to wall hurricane straps, truss plates, metal studs, gas fittings and metal flues. Smell of rot in the garage and acrid smell in the attic itself. Photos attached; what do you all think the cause could be and how would you report the condition?

Thanks, "better to error on the side of caution".

[Gunnar Alquist]

Inspected 2005 block home on a slab in central Florida and found excessive corrosion during attic inspection to all metal roof components to include shiners, roof to wall hurricane straps, truss plates, metal studs, gas fittings and metal flues. Smell of rot in the garage and acrid smell in the attic itself. Photos attached; what do you all think the cause could be and how would you report the condition?

Thomas,

How is the attic ventilation? I see soffit vents in one photo, but is there any way to exhaust? That would be my first thought. Remember, it is really not our job to determine the cause, it is our job to find and disclose it. I would probably defer to a general contractor or roofing contractor.

[Thomas McKay]

The roof is a hip style with adequate ventilation from ridge and soffit vents. I did report the condition and recommended further investigation; just woundered what you all thaught?

[Charlie Crouthamel]

Is the house close to the beach or river? ( salt air )Or did you check for Chinese drywall?Just my thoughts!!

[Jerry Peck]

what do you all think the cause could be and how would you report the condition?

While the house may have defective drywall (what did the AHU coils look like?), you are basically in the same environment that I am (how close to the ocean is that house?), and the salt spray will get into the attic and do just what is shown in your photos. I've also seen that up and down the coast when I was in South Florida.

Sealed attics are the best thing along the coast.

[Gunnar Alquist]

Sealed attics are the best thing along the coast.

Ok JP, I'll bite.

Why? Don't you get excessive moisture in the attic when you seal them? Or do they become a part of the conditioned space?

[Thomas McKay]

Property is about 2 miles west of US 1 and 4 - 5 miles from the ocean. Done a lot of homes 30 years old closer to the ocean where the metal components look much better. Electrical panel box copper parts looked OK it was mounted in the garage on a block wall. Recent A/C problem repair person apparently said coils looked OK, A/C furnace installed in the garage. Ventilation looked good was not excessively hot on a warm day. :confused:

[Larry Morrison]

This is my opinion: The lack of insulation is allowing the warm humid air from inside the home to condense on the cold metal and corrode it.

Attics (especially metal components in them) will actually get colder than the outside temperature during the night, by 10-15 degrees due to radiant heat loss to space, that is about -455 degrees Fahrenheit (-270 Celsius).

[Jim Scott]

Consider checking for Chinese drywall. Smell and corrosion are signals that it is present. While we have no reported cases of it here that I am aware of, and I have never seen it. I have been asked about it and did some research. Venting and a host of other issues could be the cause, but the acidic smell would be a trigger for me.

[Jerry Peck]

Ok JP, I'll bite.

Why? Don't you get excessive moisture in the attic when you seal them? Or do they become a part of the conditioned space?

Gunnar,

I'm referring to the sealed, unventilated, attics with the insulation on the underside of the roof sheathing, yes, the attic becomes part of the conditioned space.

Actually, "conditioned space" is a misnomer for those attics as they do not have any supply source, so they were first referred to as "semi-conditioned space", but the attic were not partially conditioned either, and research showed that the temperature in the attics were typically only 1-3 degrees different that the true "conditioned space" below, and you can easily get a 1-3 degree difference between different areas of the conditioned space, so the attics have since been referred to as "conditioned space" even though they are not "conditioned".

[Jerry Peck]

Property is about 2 miles west of US 1 and 4 - 5 miles from the ocean.


At 4-5 miles from the ocean (my house is 4 miles from the ocean) there is not a lot of affect from the salt air, so I would turn toward thinking it was some other cause, and contaminated drywall is the next this I would investigate, but that usually shows up on the copper evaporator coils and ground conductors to receptacles and switches - did you check any of them?

[Mark Cramer]

Inspected 2005 block home on a slab in central Florida and found excessive corrosion during attic inspection to all metal roof components to include shiners, roof to wall hurricane straps, truss plates, metal studs, gas fittings and metal flues. Smell of rot in the garage and acrid smell in the attic itself. Photos attached; what do you all think the cause could be and how would you report the condition?

Thanks, "better to error on the side of caution".

That's not salt air. It's not from moisture condensing in the attic. It's not Chinese drywall.

Look for the source of the rot odor and acrid odor in the attic. Whatever is causing that is likely the source.

[Thomas McKay]

Is corrosion like pictured and the acid smell possibly clues this could have been a Meth House? :confused:

[Bob Harper]

If that is due to acidic corrosion all that CSST must be replaced ASAP. Type 304 stainless does not resist acid attack well--trust me. You could cut a little of the plastic jacket back to see if there is corrosion visible there. If there is, red flag it and recommend the gas be shut off at once. If not, it still needs to be thoroughly inspected and probably replaced CYA.

Look closely at any zinc coated surfaces. If you see tiny spots of white or rust, it is probably an acidic process. A little zinc oxide on galvanized steel is one thing but acidic attack is another. For one, how do you know the source of the corrosion has been removed?

I'm leanning towards the seller hiring an industrial hygienist to investigate before this house collapses or blows up.

[Thomas McKay]

Thanks for that information Bob, I have forwarded it on to the listing agent for the property; the following was his reply.

"The rust and corrosion that was present in the attic was from an old furniture mural that was used to floor the attic by the seller so he could store items in the attic. The General contractor that went behind you, verified with the builder that “Chinese Dry Wall” had not been used".

Can you believe this Realtor actually has now taken the word of the builder, a contractor who does his home inspection and did this as a favor and the previous home owner who went into foreclosure that an old furniture mural could cause this kind of corrosion? This is a sick house and the guy doesn't want to admit it; blaming me for all the troubles. :rolleyes:

[Rolland Pruner]

Chineese drywall? No or improper venting? clode to water Ocean? plumbing veting in attic? Bath venting in attic? Dryer venting in attic? I noticed no insulation??



Rolland Pruner

[Thomas McKay]

Thanks Rolland; all the interior ventilation systems were venting to the exterior; the attic was somewhat comfortable during the inspection on a warm day 90F. This is a sick house and nobody wants to take responsibility except this lowly inspector. Something going on in this attic which needs to be corrected. :confused: