Water behind vinyl siding

Found this today at a 13 year old home. I first noticed a water drop/run about halfway down siding. I then proceeded to “knock” siding and more and more came dripping out. This was only in about an 8 x 8 area and no other areas did this. There was no evidence of any moisture damage and/or moisture source anywhere. What causes this? Recommendation? BTW, there was a small gap between siding joints on the back of home with bare OSB and no visible house wrap.

You are on the south side and getting condensation or melted snow perhaps.

What was on the opposite side of the wall (bathroom or kitchen)? Without house wrap could be moisture migrating from inside the home as well. Detective work is the only thing that makes this job interesting after a few thousand. Other than that, it is the same old crap day after day…TPR valves, loose toilets, bla bla bla…

I saw a builder putting housewrap behind the osb once, he acted like I was crazy when I ask why he was doing it that way.

What would happen if it was on both sides?

Depends on the climate I suppose!

Crazy thought but would it stop moisture from transferring to the framing from the OSB ?
Yes OSB would rot but…


I do not think there is one unless you took off a section to look at what is behind it to determine an issue.Siding is not a water barrier.
As long as it is not migrating to the sheathing underneath it there is no real issue that I know of and you could also post this at “your leaking house” forum…

If you install house wrap in 2 side it traps the moisture.
Mold, swelling of board, lose of strength, rusted hardware, etc.

1:Look at the gutter.
They are stained.
They obviously overflowing due to blockage, improper angel, etc.
Water can be blown onto the siding or carried behind saw-fittings.
Likely not the cause. BUT

2: Gutter nails and coils can cause a problem if not angled downwards.
If the bushing, made with a aluminum wraps. ( a coil of 28 or 30 gauge )coiled aluminum 4-5 inches long and use to separate the gutter walls as the are installed into rafter ends ** hopefully… **
If the nail is sloped upwards the water is carried onto the nail through the coil to the back side of the gutter walls that has a hole in it., So through the backside of the gutter walls, to behind the roof saw-fitting and behind the sidling.
I have repaired this several time .
What to look for.
Nails aimed upwards , should be level of slightly downwards at 5 degrees.
Look at saw-fitting for staining,( like the gutter staining ) in location of the dripping water from siding. Look up and investigate the nails.
reset and re-angled all nail.
Take a 2 to 4 foot level and see if the gutter are aimed in the right direction.

You can guess all you want but unless you have a look under the siding all you are doing is just guessing.

Vinyl Siding installed without a vapor barrier (over bare OSB) is improperly installed.

Needs replacement.

Linas I am not guessing.
I am posting observations I experienced working with said product.
I installed siding and roofing and repaired for 15 plus years. 3 trades 15 years Brick roofing siding.
If you noticed I pointed at what to look for.

Now that I re-read the original post, Joshua mentioned that he did not observe any house wrap so Joe wins the prize for this one. No guessing.:wink:

Halt the presses.
There may be nothing wrong with using it underneath also.

DuPont™ Tyvek® can be used either over or under sheathing. When DuPont™ Tyvek® is used under sheathing, it functions only as an air barrier and does not protect the sheathing as a secondary water barrier. DuPont™ Tyvek® has been used directly over studs where there is no sheathing, although use of sheathing is a highly recommended building practice.

Are you stalking me Bob?

Please bob.
It was stated 2 sides like a sandwich
.DuPont™ Tyvek® can be used either over or under sheathing.

I do not mind being heckled for things I have not experienced that often of have been improperly trained at. No big deal…
It was my trade. Sorry.
We use Tyvek. Friends father was the complaints guy.at DuPont. Best friends uncle. Turned me on the shingle 3 years after IKO was banned. Du-point holding yard is 2 miles from my home.
Have used Tyvek scene 1986.
Sorry but a long Fu-king day
Also dependent on the sheathing to be used on the upside. Has to with stand moisture.
I could be mistaken you are sending me back 20 plus years.
Last siding job was 5 sq. of vinyl replacing tin. Reclaimed tin at salvage yard for 180 dollars. All Tyvek. Gable North side 2003. Dorval Montreal Quebec.
Owner said Robert whats that?, there was nothing before.
Not many used it but I always did.
Now everyone uses.
I replied. I bet your home uses energy and has clod floors on thet side of house.

Pottie mouth.