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.

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Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.