Standard Attic Insulation R Value

R value measures how well certain building insulation materials can resist heat.

Standard attic insulation r value.

Your home s age if your home is more than 10 year old you likely need more insulation. In general an attic s r value should be between r 30 and r 49. In general to optimally isolate an attic on average an r value of the insulation is required ranging from r 50 to r 60. However this value varies not only on the basis of the type of insulating material but also on the area.

When determining how much insulation you need don t guesstimate calculate. The higher the r value the better the thermal performance of the insulation. In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7 along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system. As a benchmark one inch of solid wood has an r value of 1.

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. Insulation level are specified by r value. Recommended home insulation r values. In particularly cold climates you might go up to r 60.

The table below shows what levels of insulation are cost effective for different climates and. R value is a measure of insulation s ability to resist heat traveling through it. Let s say the insulation you ve selected has an r value of three per inch and. The further north northeast you go the colder it is and the more necessary r value will grow.

The higher the r value the greater the insulation performance. While wall insulation is limited by the width of the studs different materials provide higher or lower 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. Average ratings the r value for cellulose insulation in an attic depends on several factors including the size shape and construction of your attic typical weather conditions where you live any.

Where you live different climates require different insulation r values. 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.