Best Insulation For Walls R Value

If you need an r value of 21 to insulate your walls you would need about six or seven inches of fiberglass batts.
Best insulation for walls r value. Of all the materials sprayed foam offers the highest r value per inch. However homeowners may have a different preference based on budget. Best insulation for 2x4 and 2x6 wall studs. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.
R value is a measure of insulation s ability to resist heat traveling through it. 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. 3 1 2 inches two by four 2x4 stud walls. 3 1 2 inches two by four 2x4 stud walls.
For example a wall with 3 fiberglass batting r value of 10 8 11 9 may have an overall r value of nearly 14 because of siding sheathing and drywall. The table below shows what levels of insulation are cost effective for different climates and. 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. The higher the r value the better the thermal performance of the insulation.
The ideal attic insulation r value is different than the ideal wall insulation r. Insulation level are specified by r value. 6 1 4 inches two by six 2x6 stud walls. See the department of energy s doe ranges for recommended levels of insulation below.
3 1 2 inches two by four 2x4 stud walls with true 4 inch depth. Appropriate for this wall type. 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.