Thread: Radiant barrier delamination

Does anyone know of any particular defect that is associated with radiant barrier decking where the foil comes off?
I'm thinking it is likely the result of wetting during construction but thought I would run it by the brain trust.

Similar Threads:

• Pink Vapor Barrier
• Crawl space moisture barrier
• Vapor Barrier Needed?
• Vapor barrier tacked to crawl decking
• Vapor barrier not required w/ Hardi Plank?

I've always wondered why it didn't fall off, given that the adhesive is subjected to such a wide range of temperatures, humidity, gravity, and different coefficients of expansion and contraction than the wood it is adhered to.

I figured the reason it didn't fall off was because it was held tight between the structural panel and the trusses/rafters.

Originally Posted by Jerry Peck

I've always wondered why it didn't fall off, given that the adhesive is subjected to such a wide range of temperatures, humidity, gravity, and different coefficients of expansion and contraction than the wood it is adhered to.

I figured the reason it didn't fall off was because it was held tight between the structural panel and the trusses/rafters.

This is the first widespread failure of this type that I have noticed. This house was about 8 years old.
I did not look close enough to tell on this but I know at least one brand is pin pricked to prevent it from being a vapor barrier. I would guess the lack of pin pricks would cause the stuff to blow up like a balloon during an inward thermal drive. Even with this failure, I'm a big fan of radiant barrier applied at the factory, much better performance than any other radiant barrier I am aware of given the lack of installation competence I usually see with radiant barrier.

Originally Posted by Jim Luttrall

This is the first widespread failure of this type that I have noticed. This house was about 8 years old.
I did not look close enough to tell on this but I know at least one brand is pin pricked to prevent it from being a vapor barrier. I would guess the lack of pin pricks would cause the stuff to blow up like a balloon during an inward thermal drive. Even with this failure, I'm a big fan of radiant barrier applied at the factory, much better performance than any other radiant barrier I am aware of given the lack of installation competence I usually see with radiant barrier.

I would say that it was an actual factory defect, a problem with the adhesive or the way it was applied to the OSB. The "pin pricks" (perforations) are there mainly for roof leaks, or rather so you will be able to see where the problem "actually is". The perforations also prevent rot by not letting moisture build up in the wood in case of a small leak (seep) that would normally go undetected but would lead to rot if moisture is trapped for long periods of time.

Edited: In looking at the pictures again. I'm wondering if the sections of the RB that are falling, are pieces that were installed on the OSB at the job site? As if they may have been short a few sheets and pieced it on without adequate stapling. I cant make out if the writing on the fallen RB if it is the same as is on the OSB. If you look there does not appear to be any RB on the OSB under the insulation baffle.

high humidity in the attic is my guess it...... couldn't hurt to have a ridge vent on this house

You may have a warranty claim: http://www.norbord.com/images/Solar20Yr_Warranty_Jul04.pdf

I don't know about a brain trust, but it seems to me that if it got wet enough for the foil to just fall off, the rest of the OSB would be very swollen and unusable.

It's almost as if that particular batch didn't get a good gluing from the mfr.

Originally Posted by Gary Smith

You may have a warranty claim: http://www.norbord.com/images/Solar20Yr_Warranty_Jul04.pdf

Good info but I see holes to drive a truck through in the warranty such as "original owner" and

This Warranty does not cover cosmetic imperfections in
the Product. Nor does it cover any damage to or defects
in the Product directly or indirectly or wholly or partly
due to: (i) misuse, (ii) improper storage, transport,
handling or exposure to the elements, (iii) improper
installation, (iv) alterations or modifications to the
Product, (v) termites or other wood destroying
organisms, including mould and mildew, (vi) fire or (vii)
acts of God such as flooding, hurricanes, earthquakes or
other similar natural phenomena. This warranty does
not apply to any damage to the Product, or to any
consequential damage, resulting from or caused by
mould and mildew.

But I will pass this along to my client.

JL,

One of the radiant barrier deck products had a server de-lamination problem many years ago and I noticed a lot of the product when I was living/inspecting in the Houston market.

I think it was Tech-Shield, but I don't recall for sure.

They had some problems at the factory and the radiant barrier backing was not adhering well at all.

And anytime it was not handled properly before install and got wet the problem was multiplied.

They took care of the problem in pretty short order and have not seen it again.

Your timeline of the property ties in about the time I was in Houston ... give or take a tad.

Was the product Tech-Shield?

Originally Posted by Nolan Kienitz

JL,


Was the product Tech-Shield?

I saw "Solar Board" and Norboard, not Tech Shield.

I think there is evidence that it is not de-lamination from the OSB but what you are seeing are pieces of radiant barrier installed after the roof deck sheeting was installed.

I would guess they were short a few OSB sheets that had the radiant barrier laminated and had someone "staple" pre-cut 22 inch wide radiant between the rafters. (as an insulation contractor, we have seen this and have installed radiant barrier where they were short on pre laminated OSB and or at gable ends)

Evidence as noted on attached picture;
No Radiant Barrier is seen between insulation baffles and roof deck. (Radiant barrier (here) installed even after baffles were installed)
Also even if the radiant Barrier had de-laminated from the OSB, it would still be held by (or pinched) at the rafters.

-----
Also noticed in the OP's photos where the rafters do not meet up with the oposing rafter, but are stagered...Is this a problem? Not sure if I have seen this before.

Originally Posted by Larry Morrison

I think there is evidence that it is not de-lamination from the OSB but what you are seeing are pieces of radiant barrier installed after the roof deck sheeting was installed.

I would guess they were short a few OSB sheets that had the radiant barrier laminated and had someone "staple" pre-cut 22 inch wide radiant between the rafters. (as an insulation contractor, we have seen this and have installed radiant barrier where they were short on pre laminated OSB and or at gable ends)

Evidence as noted on attached picture;
No Radiant Barrier is seen between insulation baffles and roof deck. (Radiant barrier (here) installed even after baffles were installed)
Also even if the radiant Barrier had de-laminated from the OSB, it would still be held by (or pinched) at the rafters.

-

Nope, just optical illusions in the photos. There were lots of other places where the barrier was visibly loose from the decking but still in place. These were just the only two spots that the barrier was not held in place by the rafters. The radiant barrier was definitely not installed separately from the decking but was "Solar Board" throughout the attic.

As you're in Texas, I'm guessing heat. The foil is at the hottest part of the roof. No better way I know to peel an adhesive than heat. I've always liked the radiant barrier applied separately, rolled over the existing insulation, in combination with ventilation (active or passive). I haven't seen any longitudinal studies on radiant barrier backed sheathing, so not sure how well they hold up. Maybe they've just assumed the rafters/trusses would hold it in place.

This is just a case of poor lamination at the factory. Someone was not doing their job watching the machinery.

In all cases where I find radiant barrier on the OSB you could not scrape it off the OSB. Heat has nothing to do with it, or moisture or freezing of moisture or you would see it hanging off the OSB in every home.

There are certainly plenty of baffles below for air circulation and the OSB does not appear to have gotten saturated in the slightest.

Simply a factory problem that there may (but I doubt it) be a factory allowance of some kind to rectify the concern or add another barrier.