Doug Miller wrote:

In article , "Pete C." wrote:
Doug Miller wrote:

In article , "Pete C."
wrote:
I think the chance of it being chemical related are close to zero. If it
was a chemical that got on the surface of the siding there is virtually
no chance that it would have any effect on the tyvek underneath.

"Virtually no chance" is completely incorrect. Vinyl siding is *not* air-tight
by any means. Solvent wiped or sprayed on the outside would very rapidly lead
to solvent vapors on the inside.

Not in enough concentration to affect the tyvek. Solvent on the outside
would almost entirely evaporate on the outside as well.

Got any data behind that assumption, or are you just guessing? Even a light
breeze could easily push solvent vapors through the gaps in vinyl siding --
that's why the Tyvek is there, because the stuff is so leaky.

The reason the Tyvek is there has nothing whatsoever to do with the
siding being "leaky". The Tyvek it there to block air infiltration while
allowing water vapor to pass preventing condensation buildup within the
walls. Vinyl siding is specifically vented to prevent condensation
buildup behind it, traditional wood siding or shingles are similarly
ventilated due to their lap joints.


Sure you'd get a
detectable amount on the inside if you were sampling the air inside,
but certainly not enough to do the damage seen on the tyvek.

How are you going to get a detectable amount on the inside if it almost
entirely evaporates on the outside? If you can get a detectable amount on the
inside

Inside as in behind the vinyl siding, not inside the house. The vinyl
siding has vent slots at each lap location just as traditional wood
siding effectively does. Of course you will get detectable amounts of a
solvent behind the siding, but detectable and sufficient to affect the
Tyvek are not even remotely synonymous.

-- after it's passed through the siding, the Tyvek, the sheathing, the
insulation, the drywall, and a layer or two of paint -- how can you possibly
think that there "certainly" wouldn't be enough to damage the Tyvek?

I never said that solvent applied to the surface of the siding would
ever make it past the Tyvek, OSB, etc., that is your moronic assumption
and entirely false.

Do you
have any data behind that assumption, or are you just guessing again? Do you
even know how much solvent, or what type of solvent, it takes to do that?

You're the only one making unfounded and dangerous assumptions. Suggest
you stick your head back up your butt and stop endangering people by
suggesting they ignore signs of a possible fire hazard in their wall.


Look, I'm not saying that he absolutely shouldn't open up the wall -- just
saying that he should look at the back side of the vinyl siding first, which
he does not appear to have done. Somebody asked him a couple days ago what the
back side of it looked like; as far as I can tell, he hasn't answered that
question yet.

And I've noted that looking at the back of the siding is not likely to
show any discoloration since it was not exposed to direct flame, it was
exposed to moderate heat, heat that will deform the vinyl siding well
before it discolors it.

Suggest you go to your local building supply place and get a sample of
vinyl siding and a piece of OSB. Place the siding on top of the OSB in
your oven and start baking it at the lowest temp, say 150-170 degrees.
When the siding starts to sag check the back for any discoloration.


It's also been suggested to the OP that he perform a test on a scrap of
siding, to see if the stain and the solvent he used will produce similar
damage. He hasn't yet reported results of that test, either.

The solvent use in question was many months ago, and the damage to the
siding was obvious enough that it is very unlikely it went unnoticed all
those months.


Both you and the OP have got the idea so firmly fixed in your heads that a
heat source inside the wall is the only possible cause of this problem, that
neither one of you is the least bit willing to entertain any alternative
explanation.

No, we have objectively analyzed the available information and concluded
that an internal heat source is the most likely cause. The relative
location of the damage vs. the electrical boxes, combined with the
notable extra nail in that immediate area further support that
conclusion. Giving the significant risk of the likely cause, that avenue
needs to be investigated immediately.

Pete C.