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Robert Holmes Posted: Jul 22, 2011 11:42 AM	Need Help Just looked a a owners home where he put the following system in by himself on all walls and in the attic Siding,Tyvec,Osb,1 inch blue board foamed to the osb in the cavity,R-13 batt taped to studs,1/2 inch blue board on face of studs,Reflective foil paper over blue board,1/2 inch strips of blue board screwed onto studs to create air gap then drywall. He wants us to apply a blueskin permeable barrier on the exterior as hes is experiencing draft. I think I should runaway, I want to propose to rip it all out and spray foam everywhere any thoughts
mason Posted: Jul 22, 2011 02:28 PM	Lets see if I got this right. He has housewrap, foam board, reflective foil over the foam board, fiberglass between the studs, foam board over the studs and he has air leaks through the assembly. Sounds like he was trying to reduce thermal bridging, radiant heat, and air infiltration but got carried away. I agree that sprayfoam could take care of most of his problems, but I would want to know specifically where the air infiltration is to make sure you seal the assembly. I suggest you get an infrared scan of the wall assembly and see where the air infiltration is coming from. Then you can make a decision how much of the mess you can leave alone and how much you have to remove. For example, it is not a bad idea to have foam board on the exterior of the OSB. Stops a lot of thermal bridging. But, I don't see the point of the reflective barrier and foam board on the studs if you use sprayfoam.
Robert Holmes Posted: Jul 22, 2011 03:05 PM	Thanks for your input, I have a camera and will start there and see what I find.

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Comments

Robert Holmes

Posted: Jul 22, 2011 11:42 AM

Need Help

Just looked a a owners home where he put the following system in by himself on all walls and in the attic

Siding,Tyvec,Osb,1 inch blue board foamed to the osb in the cavity,R-13 batt taped to studs,1/2 inch blue board on face of studs,Reflective foil paper over blue board,1/2 inch strips of blue board screwed onto studs to create air gap then drywall.

He wants us to apply a blueskin permeable barrier on the exterior as hes is experiencing draft. I think I should runaway, I want to propose to rip it all out and spray foam everywhere any thoughts

mason

Posted: Jul 22, 2011 02:28 PM

Lets see if I got this right. He has housewrap, foam board, reflective foil over the foam board, fiberglass between the studs, foam board over the studs and he has air leaks through the assembly.

Sounds like he was trying to reduce thermal bridging, radiant heat, and air infiltration but got carried away.

I agree that sprayfoam could take care of most of his problems, but I would want to know specifically where the air infiltration is to make sure you seal the assembly.

I suggest you get an infrared scan of the wall assembly and see where the air infiltration is coming from.

Then you can make a decision how much of the mess you can leave alone and how much you have to remove. For example, it is not a bad idea to have foam board on the exterior of the OSB. Stops a lot of thermal bridging. But, I don't see the point of the reflective barrier and foam board on the studs if you use sprayfoam.

Robert Holmes

Posted: Jul 22, 2011 03:05 PM

Thanks for your input, I have a camera and will start there and see what I find.

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