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blown-in insulation

Marlow's Avatar
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07-10-02, 07:26 PM   #1  
blown-in insulation

If I have blown-in insulation in my attic, can I add the Owen-Cornings Rolled insulation on top of that, or should I remove the old blown-in insulation first. Or... am I better off (both in terms of quality and financially) adding more blown-in insulation.


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resercon's Avatar

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07-13-02, 06:14 AM   #2  
Though contractors commonly mix different types of insulation, I would recommend blowing in the same type of insulation over the insulation you already have. The reason for it is different types of insulation have different rates of absorption and retention of moisture. It is true that insulation resists heat flow and as a result would resist condensation between the 2 different insulation materials. I look at it as, it increases the possibility of condensation may occur, even though the potential of it occurring is small.

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07-29-02, 07:55 PM   #3  

If you have 6 inches of fiber glass in the attic adding more will probably not save you enough energy to pay for the material. The incease in efficiency of R19 to R38 is about 7.5%(if you are lucky). Since the first 6 in. saves you about 80% of what fiber glass can perform at you can see the why the poor results.

You can save up to 30% + on a/c by installing a radiant barrier insulation over the top of your existing insulation.

If you want more detailed info contact me at [email protected].

Thank you for considering my opinion.

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