Update to: What could have done this to my vinyl siding?

[CraigT]

Originaal post:

There are no heat sources behind that wall besides a toaster oven that sits on the counter top and is seldom used. I would think any heat source from inside would have caused some damage to the cabinet directly above. This is new housing so the walls are insulated.

I haven't used any chemicals on the deck since the spring of '06.

Update:

I got the siding off (hey, it's been raining around here).

All the electrical wiring and connections look sound and unblemished.

The switch for the outside light is a different circuit, but that outside outlet is hooked to the kitchen circuit too.

Should I cut a 16" X 8" hole in the sheathing?

[Meat Plow]

Looks like the plastic over the the outside sheeting has been melted by heat. You've got to remember what you might have had on the deck that heated up that area. Either that or someone poured a flammable substance on it and tried to set your house on fire or vandalize it.

[<kjpro]

Hard to tell from the picture, is the OSB discolored?

[CraigT]

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 &#39;06 redused the siding&#39;s sensitivity to sunlight.

[ds549]

seen siding just like that.guy had a gas grill to close to it. HEAT!!!

[Dan Espen]

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

[CraigT]

None at all.

[CraigT]

I guaranty that this wasn&#39;t like this two weeks ago. I&#39;ve lived in the house

2 years. I have no little kids nor do my older children hang around on the deck. I charcoal grill about 18 feet from where the damage is.

[Meat Plow]

The plastic cover on the sheeting underneath the siding is melted and the wrinkles around it indicate a source of heat. You can come to any conclusion you desire but the sensible and logical answer is a source of heat caused that melting.

[CraigT]

The more I stare at this the more I think it was a lightning strike.

Notice the wrinkles in the Tyvek correspond to the indents of the siding. Yes the heat source was outside, melted the siding, and where it touched the Tyvek it distorted/melted it too.

[<kjpro]

Then cut that bitch open and see what&#39;s behind the OSB.

If it wasn&#39;t there and it just suddenly appeared... I would sure as hell be finding out what&#39;s in that wall!!!!!!

[<kjpro]

What says it wasn&#39;t from inside the wall and where the siding was touching the Tyvek, it was acting as insulation/heat sink and absorbing the heat?

In the other areas, the heat was able to be absorbed by the air and be carried off with little damage.

[Dan Espen]

No way.

Lightning would make a hole. Not heat the siding to melting point.

[CraigT]

But if the source of the heat was from the inside wouldn&#39;t we see MORE damage to the Tyvek than the siding? And, the pressboard seems to have no damage at all.

[<kjpro]

The siding could have acted as insulation and therefore the areas it touched were hotter, causing the damage.

[dicko]

I&#39;ll weigh in with my 2 cents. The pattern of melted tyvek seems to indicate an outside source of heat, a fairly diffuse source at that. The melted tyvek appears to be evenly spaced at the same spacing as the siding overlap as evidenced by some dirt streaks on the un melted tyvek. So wherever the siding came into contact with the tyvek, it melted. Where the siding was spaced away, it didnt melt.

This indicates an outside source to me. I doubt it was lightning. As some one else said, that would punch a hole. But it wouldnt just punch a hole, it&#39;d blast a hole.

I know someone who ruined an expensive swimming pool liner by using some plastic milk jugs as weights to hold the pool cover down. They focused the sun and melted right through the liner. This however seems to large for that. The heat was applied over a substantial area but focused over the largest tyvek hole.

-dickm

[dpb]

The first shows definitely the heating shrunk the Tyvek and melted some of it at the hottest point (which is where I thought it looked like the center was previously). Can&#39;t tell through that tiny little spot what the actual sheathing looks like.

Definitely need to cut the Tyvek and look under it to tell for sure what it actually looks like.

Not at all surprising the wiring at the outlets looks ok, they&#39;re removed from where the problem is visible altho certainly if they had shown something that would have been indicative.

I don&#39;t think this has any chance of being lightning, it&#39;s more indicative of a radiant heat source imo and lightning would have really charred something in all likelihood.

I kinda&#39; like Smitty&#39;s WAG -- didn&#39;t have a hanging mobile or something at some point by any chance? Don&#39;t know orientation wrt sun, but one thing the wife does that could be a problem if set in the wrong spot is brewing "sun tea" in the big gallon glass jar -- put that thing on a table outside the patio door and it would work really nice as he suggests...

I&#39;d still explore more around that area under the Tyvek and if that didn&#39;t satisfy me, it can&#39;t hurt to make the entry hole...

It should be possible to see if the charring (if any) is surface and improves from the outside in or intensifies once there&#39;s an area to look at in comparison to the surrounding area under the Tyvek, though.

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[Meat Plow]

The plastic under the siding would have been exponentially more melted had the heat source been underneath it. I doubt that lightning was the culprit, there would have been much more damage. Got any kids around who like to play with fire?

[dpb]

dpb wrote: ...

Another WAG -- didn&#39;t have a service tech or somebody doing some exterior plumbing or HVAC or other work that would have had a torch, perchance? Looks a lot like a torch laid down on a temporary bench or table pointing that way from a few feet away could have done...

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[Edwin Pawlowski]

What does the back of the siding look like? Discolored on the surface or through out the pieces?