Dan Espen wrote:

"CraigT" writes:

Sorry, we kind of went over this in the last thread. No heat source was the
cause unless I had a lightning strike.
Some felt it was my use of chemicals during restaining in the spring of '06
redused the siding's sensitivity to sunlight.

If it was chemicals, I think it would still be soft.

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.

Unlike what someone else said about the melt pattern in the tyvek
doesn't appear to align with the siding pattern, even if it did, if
where the siding was pressing the tyvek against the sheathing the tyvek
melted that would indicate heat from inside to me since the joint
section of the siding would be dripping goo before it transferred enough
heat to melt the tyvek.

If it were me, I'd have that wall open in about thirty seconds to see
what the hell is going on inside it, first since patching some sheathing
is no big deal, and second since the melt pattern does seem to align
with one of those electrical boxes. The back of the apparent melt area
is mostly behind the counter so you may not be able to see if there is
evidence of heating on that side.

I also note the double green washered nail in close proximity to the
electrical box. It seems quite possible that one of those two nails is
in a stud and the other hit a wire going to that box and has caused an
intermittent short. With the counter on the inside of that area it's
also possible someone used excessively long screws fastening the base
cabinets and hit a wire from that side.

I'd consider it serious enough to warrant immediate opening of the wall
cavity. It may be evidence of an actual fire in the wall that may have
self extinguished.

Pete C.