# Improving attic insulation - mansard roof



## Windows on Wash (Aug 30, 2011)

You will need to extend them far enough to where they won't be blocked by the R-50.


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## VitoB (Nov 30, 2012)

Windows on Wash said:


> You will need to extend them far enough to where they won't be blocked by the R-50.


Appreciate the advice. 

Should I leave the fiberglass batts in there? Or is not worth the trouble of removing them?

My only concern with leaving them in is the knee walls. Ideally I would have liked to spray foam them first and then blow the cellulose on top of that.


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## Windows on Wash (Aug 30, 2011)

Blow over the top is fine. 

Kneewalls work well when you cover the entirety of the framing with rigid foam and seal all the gaps.


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## tekart (Dec 6, 2014)

*Excellent resource on building insulation*

I can recommend an excellent book that not only covers interior building insulation but all aspects of building energy efficiency. It is called: "The Visual Handbook of Energy Conservation: A Comprehensive Guide to Reducing Energy Use at Home" by Charlie Wing. I cannot recommend this book highly enough for anyone looking to improve the efficiency of their building. It is literally packed with graphics, charts, and plain language explanations of how and why building insulation works


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