Wall Insulation R Values

Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system.

Wall insulation r values.

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 down r value also known as the summer r value is a measurement of an insulation s ability to resist heat flow from coming into the house. 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.

Insulation ratings can be improved by adding more layers of insulation. The ideal attic insulation r value is different than the ideal wall insulation r value. 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. Make sure your home is properly insulated in all these locations.

You can mix the type and material of insulation too. In simple terms r values measure the effectiveness of insulation and a higher number represents more effective insulation. Insulation level are specified by r value. For instance if you have a material with an r value of 12 attached to another material with an r value of 3 then both materials combined have an r value of 15.

Additional r value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included such as 1 solid foam polyisocyanurate r 8 extruded polystyrene r 5 expanded polystyrene r 4 or 1 of perlite r 2 7 and for an exterior air film winter no wind r 0 17 an interior. Achieving greater r values in attics. R value measures capacity of an insulation material to resist heat flow from one side of a wall to another. While wall insulation is limited by the width of the studs different materials provide higher or lower r values.

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. The down r value. The reason it is sometimes. Within the r value of insulation there are three kinds of r values that are commonly used to more specifically measure heat flow resistance variables.

Try the r value calculator available through oak ridge. The higher the r value the better the thermal performance of the insulation.