Vinyl Siding what lays beneath!

[bdoles2]

I came across this yesterday for the first time. So I hope I can get some good discussion [and answers].

This home is a 2 story vinyl clad home with a brick veneer on the front. The distance between each home is approx. 15 feet. The neighboring home is vinyl clad as well. Here's my question, the exterior wall that faces the neighbors home has 1/2" sheetrock under the vinyl siding, then the typical OSB sheathing under that. All other exterior walls are sheathed with just the OSB, no sheetrock. I got curious and checked the neighbors exterior wall and it is sheathed the same, vinyl/sheetrock/OSB.

I can only guess that this is some sort of "fire" code. I couldn't find the exact code in the book [I'm sure I overlooked it]. My problem was that there were several gaps and seperations between the vinyl and the sheetrock, exposing it to the elements.

As seen here -

Front and rear view of exterior -


Thoughts, comments !!!?

[Joe Funderburk, CMI]

Dyslexic contractor is my guess.

[Larry D. Kage]

Vinyl siding is not water proof...gyp board will soak up the moisture and fall apart.

[bdoles2]

Originally Posted by lkage

Vinyl siding is not water proof...gyp board will soak up the moisture and fall apart.

It's also a great area for mold to have children.

[Emmanuel J. Scanlan]

The Gypsum Association does provide guidance for the use of gypsum board as a substrate for exterior cladding. The standard number is GA-253-07, Application Of Gypsum Sheathing. There are requirements for its use as defined in this publication. There is also one type of gypsum board (identified with a brown paper face) that was made for this purpose. It was mainly for use in soffit areas but may now be fully approved as a substrate (when properly installed) for exterior claddings.

The Gypsum Association also makes sure to point out that the manufacturer of the exterior cladding will specify if their product is suitable for use with a gypsum substrate.

[cfuoco]

My guess would be a fire separation based on the proximity of the buildings and a builder who didn't know exactly how to achieve it.

[Carl Brown]

Originally Posted by lkage

Vinyl siding is not water proof...gyp board will soak up the moisture and fall apart.

And so does the OSB!

[bdoles2]

Originally Posted by escanlan

The Gypsum Association does provide guidance for the use of gypsum board as a substrate for exterior cladding. The standard number is GA-253-07, Application Of Gypsum Sheathing. There are requirements for its use as defined in this publication. There is also one type of gypsum board (identified with a brown paper face) that was made for this purpose. It was mainly for use in soffit areas but may now be fully approved as a substrate (when properly installed) for exterior claddings.

The Gypsum Association also makes sure to point out that the manufacturer of the exterior cladding will specify if their product is suitable for use with a gypsum substrate.

Good info..thanks !!

[Larry D. Kage]

Originally Posted by carl brown

And so does the OSB!

Yes...verticle mulch, Scott Wood was fond of saying.

[Peter C. Russell]

Originally Posted by lkage

Yes...verticle mulch, Scott Wood was fond of saying.

Good quote Larry, This would be a great IR scan.