I like our gc but he.
Attic insulation r38 vs r49.
I have a 6 year old home with about 12 inches r 30 of blown in insulation in the attic.
Here s what i mean.
Square feet of house or area to be insulated current and desired r value for insulation and type and cost of your energy.
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Whoa whoa david oswald you ve just entered the domain of the law of diminishing returns.
Our gc says r 38 is what they usually use in this area and that s good enough.
I ve read it should be r 49 or higher for optimal effectiveness.
Get free shipping on qualified r38 r49 insulation or buy online pick up in store today in the building materials department.
The law of diminishing returns tells me that r49 isn t much better than r39 and r60 probably even more so.
30 grains of black powder will drive that lead ball just fine.
Sixty grains even faster.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
R49 to r60 r38 to r49 r25 to r30 and add r5 to r6 insulative wall sheathing beneath the new siding 6 7 8 whenever exterior siding is removed from an uninsulated wood frame wall drill holes in the sheathing and blow insulation into the empty wall cavity before installing the new siding.
Existing 3 4 inches of insulation.
Take a look at the bigger picture and see whether you might be better served by reducing the size of the home finding ways to save on water heating appliances and plug loads or.
90 grains might be approaching the ma.
Add insulation to attic.
We re having our attic blown w insulation.
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