Attic Insulation R38 Vs R49

30 grains of black powder will drive that lead ball just fine.

Attic insulation r38 vs r49. Here s what i mean. So a ceiling with r 38 insulation will have a total r value of about 43 i e 38 5 and will let through about 5 43 or about 12 of the amount that an uninsulated one will. Wall insulation whenever exterior siding is removed on an. The law of diminishing returns tells me that r49 isn t much better than r39 and r60 probably even more so.

Recently door to door sales representatives for an insulation company offered a free inspection and quote to add additional insulation. Eere information center 1 877 eere info 1 877 337 3463. Existing 3 4 inches of insulation. 90 grains might be approaching the ma.

Whoa whoa david oswald you ve just entered the domain of the law of diminishing returns. First things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation. A ceiling insulated with r 49 insulation will have an r factor of about 54 i e 49 5 and let through 5 54 of the energy or about 9. Those up north will want anything from r49 to r60.

While there are also insulation recommendations for walls and floors this article will deal mainly with the oft overlooked attics. Add insulation to attic. 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. I have a 6 year old home with about 12 inches r 30 of blown in insulation in the attic.

Inspecting your attic insulation. Get free shipping on qualified attic r38 fiberglass insulation or buy online pick up in store today in the building materials department. Sixty grains even faster. Your attic should have a certain amount of insulation in it and the recommended level of insulation for your attic is dependent on where you live.