Plastic vapor barrier installled over floor joists in crawlspace

[Trent Tarter]

I inspected a home a while back and called out plastic vapor barrier that was installed over floor joists, floors were insulated, no vapor barrier on ground. Sellers told clients that is was code at time the home was built, I also heard that the builder argued with city building inspector about installing the vapor barrier over floor structure. I disagree and do not believe that this should have ever been allowed. The vapor barrier in not installed toward heated space and can cause moisture to accumulate in floor structure.

[Mike Lamb]

You are right.

[Jack Feldmann]

Its the way they do mobile homes all the time.

[Trent Tarter]

Its the way they do mobile homes all the time.

As you know a mobile home is built quite differently that a stick build home, especially the floor structure. As far as I know the underbelly covering on a mobile home can breath a little, not like standard plastic sheeting, also it's not attached directly to floor joists.

[John Kogel]

As you know a mobile home is built quite differently that a stick build home, especially the floor structure. As far as I know the underbelly covering on a mobile home can breath a little, not like standard plastic sheeting, also it's not attached directly to floor joists.

Trent, I agree with you in principle, but ...... have you ever crawled under a mobile home that had a plumbing leak? That big black bag, anchored by the steel frame, can hold a ton of water. If you need pics, I got 'em in the archives.

Also I agree, poly under the floor insulation is wrong, wrong, wrong, but I have seen it done with no ill effect , no sign of moisture trapped in there. That is what I have told my clients, it is wrong because it could trap moisture. However there is no sign of any moisture, so just lucky it's all dry in there.

[Scott Patterson]

Trent, I agree with you in principle, but ...... have you ever crawled under a mobile home that had a plumbing leak? That big black bag, anchored by the steel frame, can hold a ton of water. If you need pics, I got 'em in the archives.

Also I agree, poly under the floor insulation is wrong, wrong, wrong, but I have seen it done with no ill effect , no sign of moisture trapped in there. That is what I have told my clients, it is wrong because it could trap moisture. However there is no sign of any moisture, so just lucky it's all dry in there.

A word of caution! Never, I repeat Never poke your finger in the bulging belly wrap of a manufactured home!

[Rick Cantrell]

A word of caution! Never, I repeat Never poke your finger in the bulging belly wrap of a manufactured home!

That's like saying don't pop the bubbles on bubble wrap, you just can't resist it.

[Trent Tarter]

Yea I've seen plenty water balloons below mobile homes in my time.

[Larry Morrison]

Plastic Sheeting does not meet the required flame spread to be placed in that location. That alone should be of concern, just as with Kraft faced batts. It is a fire hazard.

[John Kogel]

Plastic Sheeting does not meet the required flame spread to be placed in that location. That alone should be of concern, just as with Kraft faced batts. It is a fire hazard.

That's a good one to remember, thanks, Larry.

[Rich Goeken]

A word of caution! Never, I repeat Never poke your finger in the bulging belly wrap of a manufactured home!

That's like being in an old army tent in a rain storm and touch the canvass......