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Celotex Thermax


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12-22-00, 07:03 AM   #1  
I can only insulate to an R value of 11 on my roof since the rafters are not wide and the vents take up room. Should I use Celotex Thermax over the insulation? This will increase the value to R18 but will cost half of what it is costing me to blow insulation in all the walls and blanket and vent the roof! Thanks for your help. Linda

 
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12-22-00, 11:43 PM   #2  
I'm missing something here. Why are you limited to using R-11 (or R-13) in the attic? (I'm not aware of any area in the country that doesn't require a minimum of R-19 in the attic.) "The rafters aren't wide" -- you mean they are 2X4's? Fine. So are mine. "Vents take up room" -- Your HVAC ducts in the attic? So do mine. But I have R-30 to R-38 throughout my attic (blown-in cellulose, 10" - 12" deep.) And for only twice what the Celotex would cost, you're getting your WALLS AND ATTIC blown, AND VENTS ADDED?? Why not spend an extra couple hundred dollars and have another 6" blown into the attic? That has to be a lot less expensive than the Celotex!!

 
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12-23-00, 02:40 AM   #3  
Of course this is your home, and you can do what you want. However, we are trying to tell you what is best. It sounds to me your trying to go cheap. Cheap costs money. Lefty is correct. Blow in cellolose. We would not steer you wrong.

 
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12-23-00, 08:20 AM   #4  
I'll explain what I am trying to do. Please tell me if you think it is a good idea. I am trying to use the knee-space for storage. I am planning to build short closets into that space and put file cabinets into those walls. So I do not want blown in stuff there yet. I am planning to put blanket insulation on the floor of the knee space myself until I can get a carpenter here, and I will then blow in stuff behind the closets. I am not trying to cut corners. It is just that every contractor I bring in tells me a different story which is why I am writing here. You have nothing to gain by telling me one thing rather than another - I think.
The insulation people came today and instead of cellulose blew in blow wool. They were nearly done by the time I realized it wasn't what we had agreed upon. It is toasty here now, but do you have opinions on blow wool?
Thanks and Happy Holidays!

 
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12-23-00, 04:12 PM   #5  
In my opinion - any insulation is better than none at all. Loft is the key to any blown insulation, regardless of whether it is fiberglass, wool, or cellulose. If they blew in an R-30,it is an R-30.

 
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