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Daniel Page Posted: Apr 12, 2017 03:43 PM	Shrinkage of closed cell foam / some areas now sheetrocked As others have experienced my closed cell foam insulation in the attic has pulled away from the joists in many areas, while some areas seem to be sealed well with no evidence of any issue. The area having the worst problem occurred when the contractors equipment was having an issue which forced a delay in completing the work while the failing component (the equipment that mixes and feeds the foam) was repaired. In addition in two areas the the renovations to the house turned old attic into two finished rooms: the areas 6-8 feet above where the joists meet the bearing outside wall are now sheet rocked: i.e. the area which is now "under" the roof "/-\" cannot be inspected to determine the potential / extent of any problem. The finished areas were in sections where the foam which can be still inspected showed the least problem (little to none). As others have noted in similar problems the worst of the separation seems to occur about 4s- 6ix to eight above the floor. The interior finishing was done some 2-3 months AFTER the foam had been applied and had shown no signs of any problem with pulling away. As soon as I discovered the issue in the exposed areas I contacted the contractor and he has come out for an initial look at the problem areas. I am extremely concerned that if I do not insist on the sheet rocked areas being torn out and the extent of the problem which may exist in those areas determined I will have problems in the new rooms. While some reduction in the effectiveness of the insulation "R" value in those two rooms would be OK I guess, I do NOT want to have an issue with condensation / mold / etc. I have reviewed the problems and the recommended remedial work (45 degree cut away and respray. etc and that WILLl be done for those areas that can still be accessed. My issue is what steps are needed in the two finished rooms... do we need to take out the ceiling sheetrock? What are the potential problems if we do NOT... I would, of course, prefer not to have to endure ripping out the ceiling and then redoing the rooms. My thanks for any words of wisdom/advice the folks on the site can offer in this situation.
mason Posted: Apr 12, 2017 09:52 PM	An inspection by a knowledgable spray foam person can help identify areas that require remediation. I do quite a lot of this type of inspection to determine extent of problem areas and recommendations for remediation. Contact me at masonknowles@aol.com. phone 571-239-5221.
mark moyer Posted: Apr 15, 2017 12:11 PM	dan, fix the small areas of shrinkage with gun foam or a froth pak,,or ,,god forbid,,,stuff it with filterglass. the costs and hassle of remediation will not afford you a noticable increase in performance in this assembly. i wouldnt worry about it behind the finished surface, unless you are seeing collapse of maybe 2" or more in the area's you can see. think about it, you have a pretty solid insulation system up there. it is not like every bit of heat is going to say "hey there's our escape hole,,,lets go...". yes you will have some loss there,,but consider if the assembly was an air permiable insulation like filterglass or celllulose you will have greater loss when compared to the foam system overall. Your system will work just fine. and regarding the mold/moisture thoughts...hmm but the neighbors home with the filterglass batts in the vault ceiling works,,,and it is air permiable, and warm air carries more moisture than cold air, and hot moves to cold, and,,,you would think it would be a mold emporium up there wouldnt ya? to paraphrase: patch what you can however you can and enjoy your new rooms. mark

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Daniel Page

Posted: Apr 12, 2017 03:43 PM

Shrinkage of closed cell foam / some areas now sheetrocked

As others have experienced my closed cell foam insulation in the attic has pulled away from the joists in many areas, while some areas seem to be sealed well with no evidence of any issue. The area having the worst problem occurred when the contractors equipment was having an issue which forced a delay in completing the work while the failing component (the equipment that mixes and feeds the foam) was repaired.

In addition in two areas the the renovations to the house turned old attic into two finished rooms: the areas 6-8 feet above where the joists meet the bearing outside wall are now sheet rocked: i.e. the area which is now "under" the roof "/-\" cannot be inspected to determine the potential / extent of any problem. The finished areas were in sections where the foam which can be still inspected showed the least problem (little to none).

As others have noted in similar problems the worst of the separation seems to occur about 4s- 6ix to eight above the floor.

The interior finishing was done some 2-3 months AFTER the foam had been applied and had shown no signs of any problem with pulling away.

As soon as I discovered the issue in the exposed areas I contacted the contractor and he has come out for an initial look at the problem areas.

I am extremely concerned that if I do not insist on the sheet rocked areas being torn out and the extent of the problem which may exist in those areas determined I will have problems in the new rooms. While some reduction in the effectiveness of the insulation "R" value in those two rooms would be OK I guess, I do NOT want to have an issue with condensation / mold / etc.

I have reviewed the problems and the recommended remedial work (45 degree cut away and respray. etc and that WILLl be done for those areas that can still be accessed.

My issue is what steps are needed in the two finished rooms... do we need to take out the ceiling sheetrock? What are the potential problems if we do NOT...

I would, of course, prefer not to have to endure ripping out the ceiling and then redoing the rooms.

My thanks for any words of wisdom/advice the folks on the site can offer in this situation.

mason

Posted: Apr 12, 2017 09:52 PM

An inspection by a knowledgable spray foam person can help identify areas that require remediation. I do quite a lot of this type of inspection to determine extent of problem areas and recommendations for remediation. Contact me at masonknowles@aol.com. phone 571-239-5221.

mark moyer

Posted: Apr 15, 2017 12:11 PM

dan,
fix the small areas of shrinkage with gun foam or a froth pak,,or ,,god forbid,,,stuff it with filterglass.
the costs and hassle of remediation will not afford you a noticable increase in performance in this assembly.
i wouldnt worry about it behind the finished surface, unless you are seeing collapse of maybe 2" or more in the area's you can see.
think about it, you have a pretty solid insulation system up there. it is not like every bit of heat is going to say "hey there's our escape hole,,,lets go...". yes you will have some loss there,,but consider if the assembly was an air permiable insulation like filterglass or celllulose you will have greater loss when compared to the foam system overall. Your system will work just fine.
and regarding the mold/moisture thoughts...hmm but the neighbors home with the filterglass batts in the vault ceiling works,,,and it is air permiable, and warm air carries more moisture than cold air, and hot moves to cold, and,,,you would think it would be a mold emporium up there wouldnt ya?
to paraphrase: patch what you can however you can and enjoy your new rooms.
mark

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