# Blowing in fill on top of existing insulation



## aNYCdb (Nov 20, 2016)

One of the things I've noticed in my new house in upstate New York is that the insulation in the ceiling is actually r-13 kraft faced fiberglass (the same that is in the 2x4 studs in the walls). The attic isn't particularly easy to access, but I some drywall down for other projects. 

Since it isn't really easy to get up and replace it all, so I was wondering if it would be worth it to blow fill in on top of it to to fill the cavities? Thoughs?


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## beachguy005 (Nov 20, 2016)

As long as the kraft faced side is down and you don't block any air vents.  I don't know the R value required for attics for your area but I had a house in Mass. and did just that.  Had 12" blown on top of the fiberglass.  Just make sure you don't want to get around up there after.  It's like crawling through snow.


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## aNYCdb (Nov 20, 2016)

beachguy005 said:


> As long as the kraft faced side is down and you don't block any air vents.  I don't know the R value required for attics for your area but I had a house in Mass. and did just that.  Had 12" blown on top of the fiberglass.  Just make sure you don't want to get around up there after.  It's like crawling through snow.



Thanks for the confirmation. Unfortunately due to the slope of various roof lines it isn't even normally accessible (I'm going to add an access hatch) so not being able to crawl around isn't going to be a problem.


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## Snoonyb (Dec 21, 2016)

Another alternative is unfaced batts, a little more labor intensive, but better control.


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## Gary (Dec 21, 2016)

The upside to the blown in on top of the existing, is the blown in will fill in all the little crevasses and gaps where the fiberglass insulation may not be fitting tight to the ceiling joists. Sort of like giving it a seal coat.


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## nealtw (Dec 21, 2016)

All good as long as the venting is maintained. I think this is to answer a deleted post.


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## havasu (Dec 21, 2016)

... and don't forget that if you have ceiling (can) lights, make sure to use sheet metal tubing to protect them if they are not IC rated recessed can lights.


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