How Much Attic Insulation R Value

Houses in a cold climate should have a minimum of r 49 in the attic which is equivalent to approximately 16 of fiberglass insulation.

How much attic insulation r value.

Attic insulation r value the insulation levels of an attic or of any part of a house are understood through the r value that is the value with which the insulating material is resistant to heat flow. For example if your home has cellulose insulation at a depth of 8 inches between the joists the attic insulation has an r value of 3 7 times 8 or 29 6. R value is a measure of insulation s ability to resist heat flow. The amount of insulation recommended for your home will vary depending on a number of factors.

The amount of insulation recommended for your home is dependent on where you live but here are some general guidelines. 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. 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. Insulation level are specified by r value.

In general to optimally isolate an attic on average an r value of the insulation is required ranging from r 50 to r 60. How much insulation should you install. The higher the r value the better the thermal performance of the insulation. Lighter in weight than cellulose or mineral wool but it settles more than those materials so you ve got to put in a thicker layer to get the protection you need.

Warmer climates only require an r 38 or higher or about 12 or more. Where you live different climates require different insulation r values. Insulation levels are specified by r value. The table below shows what levels of insulation are cost effective for different climates and.

The higher the r value the better the thermal performance of the insulation. R value is a measure of insulation s ability to resist heat traveling through it. Note from this chart that the ideal r value differs for each part of 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.

The r value of some insulations also depends on temperature aging and moisture accumulation. The r value depends on the type of insulation its thickness and its density. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. Recommended home insulation r values.

How much is enough.