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.
Attic insulation rating.
Existing 3 4 inches of insulation.
Let s say the insulation you ve selected has an r value of three per inch and you d like to achieve an overall value of r 36.
You ll need about 12 inches of insulation material.
Measure the length and width of the area you need to insulate.
Add insulation to attic.
Insulation r values vary based on the type thickness and density of the insulation material.
Typically a higher insulation r rating means better climate control and better energy efficiency for your home.
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.
Measure the area needing insulation.
An r value tells you how well a type of insulation can keep heat from leaving or entering your home.
Recommended insulation levels for retrofitting existing wood framed buildings.
Multiply the length times the width to determine the square footage of the space.
If your current insulation is only 5 inches deep you ll need to add seven inches of insulation to achieve the 12 inch r 38 rating.
If your insulation doesn t measure up and you need more installation can be done as a weekend diy project or you can call a professional installer to handle the job.