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Basement vapor barrier


Darren

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I did a professional 'flipper' yesterday. The buyer had her contractor along for the inspection.

When we got to the basement; the walls & ceilings were finished with drywall & metal studs. Some areas between the foundation wall and finished wall were slightly visible from inside the closets.

The buyers contractor stated the vapor barrier was missing from the foundation wall. He claimed this is required by code. Now I know sometimes plastic is installed against the foundation wall to help control water entry; but I don't think it's a code requirement.

I never heard or read that; in fact, last night I re-read the code and as far as I can tell, the only vapor barrier required is at the drywall with the barrier against the drywall.

Does anyone know of the 'requirement' the buyers builder is citing?

Just a side note; he also stated a roof ice shield is a code requirement; I sent him proof it's not.

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Darren,

A roof ice shield is not a NJ UCC requirement but is usually required as part of the manufacturer's roofing system warranty. If the roof leaks and the system is not installed to spec, the warranty may be voided. ALso check out R905 of the NJ IRC 2006 where there is a requirement for an ice barrier if the average temperature is below 25 degrees in January.

As far as the required vapor barrier that your client mentioned, I believe you are correct. There are comments in the International Energy Code NJ Edition (2006) in sections 402.2.8, and 402.5 about vapor barriers and moisture control. That is as close as I can find regarding this issue.

Hope this helps.

Steve

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Originally posted by Darren

I did a professional 'flipper' yesterday. The buyer had her contractor along for the inspection.

When we got to the basement; the walls & ceilings were finished with drywall & metal studs. Some areas between the foundation wall and finished wall were slightly visible from inside the closets.

The buyers contractor stated the vapor barrier was missing from the foundation wall. He claimed this is required by code. Now I know sometimes plastic is installed against the foundation wall to help control water entry; but I don't think it's a code requirement.

I never heard or read that; in fact, last night I re-read the code and as far as I can tell, the only vapor barrier required is at the drywall with the barrier against the drywall.

Does anyone know of the 'requirement' the buyers builder is citing?

Just a side note; he also stated a roof ice shield is a code requirement; I sent him proof it's not.

A vapor retarder should be installed on the warm-in-winter side of the insulation. Your jurisdiction could have additional requirements, you would need to check with the AHJ about the additional barrier on the foundation wall. Or you could ask the contractor to cite the code for you.

Unless the cavity is vented, I would favor vapor retarder only on one side.

The ice shield is a requirement in some jurisdictions. Again, you will need to know what your jurisdiction requires. The IRC leaves it open for the AHJ to call.

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Steve,

I read the energy code and Section R318 of the IRC; that's where I came up with no plastic required on the foundation wall.

Now, the ice barrier; the roof was newly covered with this fake slate, it kinda looks like plastic. I'm doing research now; this is the first time I came across this material. Anyone else seen this?

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Originally posted by Darren

Steve,

I read the energy code and Section R318 of the IRC; that's where I came up with no plastic required on the foundation wall.

Now, the ice barrier; the roof was newly covered with this fake slate, it kinda looks like plastic. I'm doing research now; this is the first time I came across this material. Anyone else seen this?

Lamarite is commonly used as a substitute for slate. We have successfully specified this product on homes:

http://www.tamko.com/OurKeyBrands/LAMAR ... fault.aspx

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Hi,

Those are Davinci slates. Compare the pattern on the bottom-center slate in picture #7 here to the pattern on the full slate pictured just under that lifted slate in your picture and you'll see that they are identical. You can download the specs for those right there on that site.

ONE TEAM - ONE FIGHT!!!

Mike

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I can think of good reasons why one doesn't want a vapor barrier on the foundation; it will condense so much water, it can run down and look like a foundation leak coming under the wall.

I don't think the gentleman has it right.

I'd review BSD-106 from Building Science Corp and apply those principles to your conditions (I don't know what you have in Jersey).

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