Minimum R Value For Attic Insulation

Prescriptive compliance form 405.

Minimum r value for attic insulation.

Know exactly how much you need with our project calculators. Performance compliance walls ceilings floors. Insulation levels are specified by r value. The higher the r value the greater the insulation performance.

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. R value is a measure of insulation s ability to resist heat traveling through it. 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.

R value measures how well certain building insulation materials can resist heat. The higher the r value the better the thermal performance of the insulation. In zone 1 the average minimum requirement for attic insulation is 9 inches of r30 fill. Maximum 20 of conditioned floor area.

The average recommended level is 14 inches of r49. Recommended home insulation r values. 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. Insulation level are specified by r value.

The average recommended level is 17 inches of r60. Add the right kind of insulation. The table below shows what levels of insulation are cost effective for different climates and. There are many ways to retrofit a home with fiberglass and.

Raised r 13 sog r 0 windows. Your home s age if your home is more than 10 year old you likely need more insulation. In zone 2 the average minimum requirement for attic insulation is 9 inches of r30 fill. How much insulation in attic for zones 1 4.

Insulating power or r value is only one factor to consider when building or improving a home to keep it comfortable. When determining how much insulation you need don t guesstimate calculate. For block walls interior insulation must meet or exceed r 7 8 and exterior insulation must be r 6. Ceiling insulation must be much higher at r 30 and a raised floor must be at least r 13.

Where you live different climates require different insulation r values. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. 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 flow.

In general to optimally isolate an attic on average an r value of the insulation is required ranging from r 50 to r 60.