Proper R Value For Wall Insulation

R value is a measure of insulation s ability to resist heat traveling through it.
Proper r value for wall insulation. See the department of energy s doe ranges for recommended levels of insulation below. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. When determining how much insulation you need don t guesstimate calculate. The higher the r value the greater the insulation performance.
R value measures how well certain building insulation materials can resist heat. Also included is the hugely helpful insulation zip code calculator that spells out the suggested amount of r value necessary for the different portions of a structure like foundation interior and exterior walls attic and more. The most proper insulation level to use on ceilings are r 30 batts that are as thick as r 25 batts but fit into a 2x10 framing. Higher r value numbers mean that the insulating material resists the cold or heat from the outside better.
When the spec is available you can also add rigid foam insulation which increases r values and eliminates thermal bridging although this type of insulation must be covered with a fire rated material when they are. The r refers to absolute thermal resistance. 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. Other considerations may include indoor air quality impacts life cycle costs recycled content embodied energy and ease of installation especially if you plan to do the.
To choose the best insulation for your home from the many types of insulation on the market you ll need to know where you want or need to install the insulation and what r value you want the installation to achieve. Insulation level are specified by r value. Thickness density and type of materials are some factors that contribute to. However rigid foam insulation must be covered with a fire rated material when used on the interior of a building.
Recommended home insulation r values. Insulate the garage s ceiling by using the recommended r value for your area as advised by the department of energy s oak ridge laboratory. 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. Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing.
The table below shows what levels of insulation are cost effective for different climates and. Know exactly how much you need with our project calculators. R value is a standard unit of measurement for determining among many things how effective your insulation will be. If the walls and ceiling are closed in consider using loose fill insulation as this form of insulation uses a machine to get the insulation where it needs to go through a hole in the sheetrock.