While some ceilings in the southwestern part of the united states require a minimum of r 19 insulation most attics or ceiling areas require a minimum of r 38 in the ceiling.
How much r value do i need in my attic.
How much attic insulation do i need.
R value of insulation by type.
Existing 3 4 inches of insulation.
Things needed dust mask.
Learn more about insulation r values however the real answer is a bit more complex.
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.
Energystar gov for homes in the boise idaho area the insulation r value climate zone is 5.
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.
The short answer is as much as you can get and a good rule of thumb is to have a r value of 38 in your attic.
There are two factors to consider when planning to insulate your attic.
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.
See the department of energy s doe ranges for recommended levels of insulation below.
Add insulation to attic.
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.
This will allow you to add the needed insulation.
Recommended insulation levels for retrofitting existing wood framed buildings.
Where you live different climates require different insulation r values.
You will need a.
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.
I ll also make sure to have an r 25 rating for my floor insulation.