Minimum R Value For Attic Insulation

If structural sheathing covers 40 or less of the exterior continuous insulation r value shall be permitted to be reduced by no more than r 3 in the locations where structural sheathing is used.

Minimum r value for attic insulation.

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. In zone 1 the average minimum requirement for attic insulation is 9 inches of r30 fill. Ceiling insulation must be much higher at r 30 and a raised floor must be at least r 13. R value measures how well certain building insulation materials can resist heat.

Your home s age if your home is more than 10 year old you likely need more insulation. When determining how much insulation you need don t guesstimate calculate. Maximum 20 of conditioned floor area. You will need a higher r value of insulation if you live in the northeast than if you live in southern california.

Meet minimum r values given in table 402 1 1 frame walls r 13 block walls interior insulation r 7 8 exterior insulation r 6 ceilings. Insulation levels are specified by r value. Raised r 13 sog r 0 windows. R value is a measure of insulation s ability to resist heat flow.

R value is a measure of insulation s ability to resist heat traveling through it. The higher the r value the better the thermal performance of the insulation. The average recommended level is 14 inches of r49. The higher the r value the better the thermal performance of the insulation.

There are many ways to retrofit a home with fiberglass and. 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. 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. The average recommended level is 17 inches of r60.

Performance compliance walls ceilings floors. Recommended home insulation r values. Where you live different climates require different insulation r values. Add the right kind of insulation.

Know exactly how much you need with our project calculators. How much insulation in attic for zones 1 4. The higher the r value the greater the insulation performance. For block walls interior insulation must meet or exceed r 7 8 and exterior insulation must be r 6.

Insulation level are specified by r value. The table below shows what levels of insulation are cost effective for different climates and. Insulating power or r value is only one factor to consider when building or improving a home to keep it comfortable. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type.

Prescriptive compliance form 405.