You need 20 in.
Rp 30 insulation attic.
For diy attic insulation you ve got two choices.
Johns manville unfaced batts and rolls effectively control heat flow to the outside and unwanted noise inside.
Owens corning pink insulation is soft to the touch and easy to install.
Once you ve decided which type is best for you examine the material options and prices to home in on the right product.
Here s how to use 3 layers of 2 inch polyiso foam board to meet code and keep your ne.
90 grains might be approaching the ma.
The higher the r value the better the thermal performance of the insulation.
In particularly cold climates you might go up to r 60.
Whoa whoa david oswald you ve just entered the domain of the law of diminishing returns.
Both can be added to uninsulated attics or layered over existing material.
Let s say the insulation you ve selected has an r value of three per inch and.
R value is a measure of insulation s ability to resist heat traveling through it.
Kraft faced insulation has a vapor retarder that helps to control moisture.
Department of energy recommends an r 30 to r 60 for attics.
When adding a second layer of insulation in the attic always add unfaced insulation.
Loose fill or batt the common term for blanket insulation.
The table below shows what levels of insulation are cost effective for different climates and locations in the home.
Here s what i mean.
Sixty grains even faster.
Your joist cavities are completely filled lay unfaced insulation in long runs perpendicular to the joists.
Of insulation to reach an r 60 in your attic.
786 429 60.
Owens corning r 30 ecotouch pink unfaced fiberglass insulation roll 23 in.
Better than spray foam thermal break and relatively consistent r 30.
Owens corning attic insulation.
30 grains of black powder will drive that lead ball just fine.