Meat Plow wrote:

On Sun, 29 Jul 2007 18:26:32 -0500, Pete C. wrote:

Have you checked the melting point of Tyvek (polyolefin) vs. the siding
(polyvinyl) vs. the temp required to discolor the OSB siding?

No have you?

No, therefore I don't jump to conclusions like you do.

Claiming that the "plastic under the siding" i.e. the polyolefin Tyvek
would be "exponentially more melted" had the heat come from inside the
wall vs. the polyvinyl siding is rather like claiming that the silicone
baking mat would melt before the cookies on it baked if the heat came
from under it which obviously isn't true.

As for the OP's siding, tyvek, OSB and house, there is a fair amount of
evidence pointing to the likelihood of a heat source from inside the
wall and given the ease of removing and replacing a section of sheathing
and the risk if the problem is as suspected, there is no point in
looking up polyvinyl and polyolefin melt temps.

Bottom line - open the wall and see what the hell is going on.

Pete C.