Moisture Problems

[Mobile_Rookie]

We purchased a used mobile home last year and had it moved onto our property. It turns out the "contractor" we used and his "associates" were better at swindling us out of money than doing the job correctly.

We have a 16x72 1996 modular home. It is on a packed gravel pad and we had skirting built around it. The skirting is framed with 2x4's, has insulation, osb, then roofing paper to waterproof it and finally vinyl siding. There is NO poly anywhere, which we realized after we fired them should be there as well as on the ground. We got everything done right before winter and planned to install the polly this summer. When we went under the home this spring, we noticed a wet spot in the belly insulation, under one of the bathrooms. We went under again today and the wet spot seems to run everywhere the cold water line is (though that's just our guess). We noticed that the water line coming in is full of condensation and that's what made us wonder if that what the whole problem may be.

After reading a bit in the forums here, I wonder if this is condensation, if we can then solve our problems by installing a dryer vent (also not done), putting poly under the home as well as up the sides of the skirting, and maybe putting screen on our two access doors in order to vent the crawlspace in the summer.

Is there anything I'm missing here? Any advice would be appreciated!

[1987Commodore]

Generally, a wet spot on the belly would be a water leak, however, since you indicate that you have insulated skirting with no ventilation, and the dryer apparently venting into the crawl space also, you may be correct that it is just condensation.
Does the belly wrap sag down, indicating a pool of water above it? Can you see any water dripping out? Is it damp, or dripping wet?
You must have ventilation. Screening your access points is a good start. There are automatic vents available that you can install in your skirting, available from the site store, or also in home centers.

[Greg]

Hi & welcome. Is the moisture above the belly? Can you push up on it and feel water? If so you may have a plumbing leak somewhere and need to do more checking.

Ventilation should be around 1sq/ft. per every 150 sq/ft of floor area. I have panels that I open for the warm weather and replace with screens.

Venting a dryer under the home is a MAJOR no no. You need to get it routed outside the skirting.

Greg

[Mobile68]

Ventilation should be around 1sq/ft. per every 150 sq/ft of floor area.

Hi Greg.

I'm curious to know how that ratio was derived.

Also, the amount of ventilation would be dependent on the moisture levels in ones area.

[Greg]

That ratio is the recommended "standard" that has been used for years, If you do have wet location you will want more. In warm weather I personally feel that you can't have too much and in the winter you want it as tight as possible.

Greg

[Mobile68]

Well, you didn't answer my question as to how the ratio was derived lol, but I doubt anyone knows.

If however we go by that standard, does that compensate for the screen resistance?

[Greg]

No, that is 100% free flowing air. I believe that If you look at at the vent it will have an actual "free flow" size on it.

Any ventilation is better than none.

OK, This link should answer the question of where the ratio came from.
http://www.smartvent.net/docs/crawlspacestudy.pdf

Greg

[DADDYO]

I THINK I FIGURED IT CORRECTLY, SO IF I PUT SKIRTING VENTS 10X16 INCHES,2 ON EACH LONGEST SIDES OF MH 14'X61', THAT WILL BE OK ?

[Greg]

That's in the ball park, like I said ANYTHING is better than nothing.

Greg

[UmpJJ]

I have a 16 X 80, and I have 10 automatic vents installed. About $16 each at Lowes. The open automatically at a set temperature, and likewise close when it's cold. Install 'em and forget 'em!

UmpJJ