Garage Attic Insulation R Value

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

Garage attic insulation r value.

Insulation level are specified by r value. 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. Where you live different climates require different insulation r values. Recommended home insulation r values.

These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. Your home s age if your home is more than 10 year old you likely need more insulation. The insulation will keep the naturally hot or cold air in the garage and the artificially warmed or cooled air in the room above it. The higher the r value the better the thermal performance of the insulation.

If you already have drywall installed around your garage but don t have it insulated then blown in insulation may be the answer. This will serve the same function of keeping hot or cold air inside the garage as it does for the rest of the house. But if your walls are exactly 92 5 8 high buy the pre cut batts and save a little time. 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.

Most estimates for installing radiant barriers reach in the thousands of dollars. Garages typically aren t built to be airtight and have lots of air gaps to the outdoors. The table below shows what levels of insulation are cost effective for different climates and. But for the homeowner who already has r 30 to r 38 insulation in the attic it won t help much.

A garage attic also should be insulated is if there is an air conditioned room above the garage. Exterior walls if your exterior walls are constructed from 2 by 4 inch studs the most insulation that can go into the wall while retaining its r value is r 13 or r 15 as these are both made to fit a cavity. 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. If the walls are framed 24 on center or have 2x6 framing buy insulation that fills the space like 5 1 2 deep r19 or insulation that s 23 wide.

It s also important to realize the value of air sealing in conjunction with insulation. Garage walls vary in height which usually means buying rolls of insulation and cutting them to fit. A contractor will come and open up a hole in the wall pump in a cellulose insulating material and then patch up the opening. 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 in your attic to reach r 30 if you live in zones 2 or 3.