Learn more about insulation r values however the real answer is a bit more complex.
How much r value do i need in my attic.
For example if your home has cellulose insulation at a depth of 8 inches between the joists the attic insulation has an r value of 3 7 times 8 or 29 6.
This will allow you to add the needed insulation.
Where you live different climates require different insulation r values.
I ll keep in mind to have a minimum of r 49 in my attic since my house is located in a place with cold weather brrr brrr and brrr.
To determine the r value of the insulation in your attic you need to know the r value of the type of insulation in your home and the thickness of the insulation.
Add insulation to attic.
If you look at the chart above you can see that the attic should achieve an r value between r38 and r60 depending on the current insulation levels.
Typical recommendations for exterior walls are r 13 to r 23 while r 30 r 38 and r 49 are common for ceilings and attic spaces.
You will need a.
These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.
Depending on where you live and the part of your home you re insulating walls crawlspace attic etc you ll need a different r value.
I ll also make sure to have an r 25 rating for my floor insulation.
Existing 3 4 inches of insulation.
See the department of energy s doe ranges for recommended levels of insulation below.
Here are the r values per inch of the most common types of insulation.
Things needed dust mask.
There are two factors to consider when planning to insulate your attic.
For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3.
Recommended insulation levels for retrofitting existing wood framed buildings.
R value of insulation by type.
How much attic insulation do i need.