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Did I get the right spray foam?

Cherylann128 | Posted in Green Products and Materials on

Hi. First thank you to the wonderful people who contribute to this forum. I need some advice and hopefully reassurance that I did the right thing. We just had open cell spray foam installed on the roof deck of the attic, in the eves and dormer roofs of our 100 year old house. I thought I had thoroughly researched this before hand but I guess not because today I found a post here that says this is all wrong. I did ask the spray foam contractor why not use closed cell but he said that open cell was the way to go for this installation. We live in Philadelphia PA which I believe is zone 5. The post I’m referring to (that has me hyperventilating with anxiety right now) is this below.

Open-cell spray foam warning!
We live in the Pittsburgh PA area, which I believe is in climate Zone 5. This is more of a warning to anyone considering open cell spray foam, or anyone that may currently have it. We had the foam sprayed in our attic back in 2007 to including attic walls, gables, and roof decking which gave us the “closed envelope”/ un-vented attic (approx 1800 sq ft of living space). The thickness of the foam was from 6 ” to 10″ depending on the area. The gable walls were sprayed to the thickness of 3 1/2 “. Our attic is a walk-in, soon to be a future living space. December 2011 we noticed a small water spot on the floor of our attic. After removing the foam in this area, we noticed a very large air gap in which the foam was not adhered to the decking. Mold and wetness was present. The water spot was from condensation that had built up in this area.
We contacted the installer of the foam at this point. The company came back and starting randomly removing small areas of foam throughout the attic. There were several areas in which the foam was pulled away from the roof decking, and all roofing nails were rusted. Even where the foam did adhere, the nails were rusted. Many of these areas had extensive mold. There were many areas that had voids and tunneling that you would not have found until you began removing the foam off the decking. Looking at it from the living space, the foam appeared to be adhered to the substrate. All areas had condensation issues, but it seemed most of the mold was on the north side of the house. This is called north face frosting, where the sheathing does not get enough radiant heat on the shingles and frost during the winter. This creates moisture then mold. as one mold expert had mentioned which examined the attic.
Prior to removing the foam, a forensic engineer determined the mold growth on the underside of the roof decking was the result of condensation and voids between the foam insulation and the roof decking. Water vapor entered the voids between the decking and foam insulation via outside air passing through openings between the foam and the soffit vent baffles and interior air via small openings between the insulation and the roof framing. Interior moisture readings were done, and were within normal ranges. So, our house was not the cause of this problem.
All the foam was removed in July 2012. We paid out of pocket $2000 in mold remediation which the installer or the foam company took responsibility for. Having two kids with asthma and allergies, we had no choice but to get the mold removed immediately.
If you are considering open cell spray foam, you better reconsider your options. If you currently have open cell foam, you better dig deeper than just looking at it. If we had not noticed this small area of condensation, about the size of a baseball, we would have had no reason to think there was a problem. Our attic area would of been slowly but surely rotting away from mold and condensation, which was surely caused by the open cell spray foam.
Right now we have no insulation in our attic. We are considering our options. If you experienced any problems with your spray foam, or have any comments, we would appreciated it.
POSTED SAT, 09/08/2012 – 22:25
EDITED SUN, 09/09/2012 – 06:21

Can anyone tell me whether using open cell was a huge mistake and what my options are if it was? Thank you so much.

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  1. davidmeiland | | #1

    Cherylann, how thick is the foam that was installed in your house? What specific brand and product? Has anyone aside from the installer inspected the work carefully? Can you post some photos?

    The scenario described in J Murphy's post above is certainly possible, but that post describes a faulty installation, and there are probably other contributing factors as well (such as humidity levels in the house).

  2. Cherylann128 | | #2

    Thank you for your response, David. I haven't inspected it yet but I will tomorrow. I'm a little worried though because I did just inspected the job this same crew did in the crawl space of my beach house. I specifically said I wanted 2" of closed cell foam on the joists to prevent rot (the space can't be conditioned because flood vents are code) but on most of the joists its about 1/4-1/2"! I'm not feeling too confident here. I'll inspect the attic tomorrow and let you know what I find. Thanks again.

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