How Much Attic Insulation R Value

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How much attic insulation r value.

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. 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. The r value depends on the type of insulation its thickness and its density. Insulation levels are specified by r value.

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. 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. How much is enough.

Warmer climates only require an r 38 or higher or about 12 or more. 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. In general to optimally isolate an attic on average an r value of the insulation is required ranging from r 50 to r 60. The amount of insulation recommended for your home will vary depending on a number of factors.

Note from this chart that the ideal r value differs for each part of your home. When calculating the r value of a multilayered installation add the r values of the individual layers. How much insulation should you install. The table below shows what levels of insulation are cost effective for different climates and.

Insulation level are specified by r value. The amount of insulation recommended for your home is dependent on where you live but here are some general guidelines. R value is a measure of insulation s ability to resist heat flow. 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.

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. The r value of some insulations also depends on temperature aging and moisture accumulation. 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.

You will need a higher r value of insulation if you live in the northeast than if you live in southern california.