Exterior Wall Insulation R Values

Insulation applied to the exterior of foundation wa lls and around th e perimete r of slab on grade floors shall have a rigid.

Exterior wall insulation r values.

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 your attic to reach r 30 if you live in zones 2 or 3. Fiberglass batts for standard 2 4 walls are now available in low medium and high density products that range from r 11 to r 15. 6102 4 1 protection of exposed foundation insulation. Add r5 to r6 insulative wall sheathing beneath the new siding.

In most wall applications you will use r 13 or r 15 kraft faced fiberglass insulation rolls for these two by four stud walls. While wall insulation is limited by the width of the studs different materials provide higher or lower r values. The higher the r value the greater the insulation performance. Add r5 insulative wall sheathing beneath the new siding.

Wall cavity and duct distribution system insulation shall be installed in a manner that permits inspection of the manufacturer s r value identification mark. Drill holes in the sheathing and blow insulation into the empty wall cavity before installing the new siding and. Know exactly how much you need with our project calculators. See the department of energy s doe ranges for recommended levels of insulation below.

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. Wall insulation whenever exterior siding is removed on an. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. The r value of thermal insulation depends on the type of material its thickness and density.

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. Add r5 insulative wall sheathing beneath the new siding. While rated differently these two types of insulation are close enough in thickness that they can both fit into modern two by four wall systems. Add r5 to r6 insulative wall sheathing beneath the new.

When determining how much insulation you need don t guesstimate calculate. Whenever exterior siding is removed on an uninsulated wood frame wall. Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system. Installing more insulation in your home increases r value and the resistance to heat flow.

Drill holes in the sheathing and blow insulation into the empty wall cavity before installing the new siding and.