What is the difference between R38 and r49 insulation?

A ceiling with an R-value of 38 lets through only 1/38 of the amount of energy per square foot that passes through that window, or about 2.6% of the energy; a ceiling with an R-value of 49 lets through only 1/49 of the amount of energy per square foot that passes through that window, or about 2.0 % of the energy.

Is R49 good insulation?

R-49 will do a good job of protecting your ceilings from the extreme inferno-like temperatures of 130-140 degrees in your attic. Think about it. If it's 140 degrees in your attic, and you're trying to hold 75 degrees inside the house, your attic insulation has to protect you from 65 degrees of heat gain.

Is R-38 insulation Good for attic?

If your attic has little or no existing insulation, you'll want to install an R-38 rated material. If your attic has 2-3″ of existing insulation, you'll want to install an R-30 to achieve a total of R-38.

What insulation R-value is best?

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. See the Department of Energy's (DOE) ranges for recommended levels of insulation below.

How thick is R49 batt?

A: Hello Shelly, Owens Corning R-49 Fiberglas Batt Insulation is 14" thick and will be compressed if installed into a 2x10 or 2x12 rafter. Compressing insulation will reduce the R-value of the product.

Improving R-value with Radiant Barrier Over Insulation

Can you have too much insulation in your attic?

It's possible to over-insulate an attic as too much will cause moisture buildup and eventually result in mold. Eventually, adding more insulation leads to diminishing returns in trapping heat as well.

What level insulation should I use in my attic?

The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.

What is R-38 insulation used for?

10¼ ” thick, R-38C EcoTouch® Thermal Batt insulation prevents moisture damage and help assure long roof life by providing 1" of ventilation air space between the insulation and roof deck.

How do you get a R38 on the ceiling?

An insulation value of R-38 is at the high end and requires a minimum thickness of 12 inches. R-value does not depend on a single layer of insulation. To achieve R-38, you can use two layers of R-19 or three layers of R-13, which give slightly higher thermal resistance.

Is higher R-value better?

The R-value for insulation is a way to measure how much resistance the insulation has to heat flow. The higher the R-value, the more the resistance and the better the material is at insulating a home. Generally, insulation materials with higher R-values cost more when compared to those with lower R-values.

What is the R-value of 4 inches of blown insulation?

For areas with 3-4 inches of existing insulation, you will need an R-value of 38-49. For insulating flooring, you will need an R-value of 25-30.

What is the best R-value for 2x4 walls?

Insulation for 2x4 Walls

In most wall applications, you will use R-13 or R-15 kraft-faced fiberglass insulation rolls for these two-by-four stud walls. While rated differently, these two types of insulation are close enough in thickness that they can both fit into modern two-by-four wall systems.

What is the best R-value for a garage?

Exterior Garage Walls

You should be targeting an R-Value of R-13 or R-15 in these areas to properly maximize your insulation in this application.

What R-value do I need for basement walls?

The Model Energy Code recommends R-11 insulating values for basement walls in most of the country and R-15 for the northernmost states.

What insulation should I use for garage walls?

Fiberglass is the most commonly used type of insulation in garages (just as it's the most popular type in homes). It's sold in precut batts and long blankets that fit between wall studs and ceiling joists.

What thickness is R38 insulation?

The R-38 high-performance batts are 10˝ to 10-1/4˝ thick as opposed to stan- dard R-38 fiber glass insulation batts of 12˝.

Should I remove old attic insulation before adding new?

Expert contractors that specialize in insulation advise that removing old fiberglass insulation is best before installing new cellulose insulation because of possible mildew, mold, or rodent excrement.

How often should attic insulation be replaced?

As a general rule, insulation should be replaced or retrofitted every 15 to 20 years. However, it may need replacing or retrofitting sooner depending on the type of insulation installed, the R rating of the original insulation, compression and movement over time, and whether any damage has occurred.

What R-value insulation do I need in Michigan?

Michigan is in climate zones 5 through 7. For an uninsulated attic, it would require an R-Value between R49 to R60. If you have an existing 3- to 4-inches of insulation in your attic, you will need between R38 to R49. You don't always have to hit that prescribed R-Value.

Is it better to insulate ceiling or roof?

If you are deciding between insulating the roof deck or the ceiling, Insulating your ceiling should be the priority. Not only is it easier but ceiling insulation is beneficial in a number of ways: Keeps the temperature in the building regulated. Saves on energy costs.

Will adding more insulation attic make difference?

According to the Department of Energy, properly insulating the attic can save 10 to 50 percent on a typical heating bill. In the Washington area, there are many styles of homes and roofs, but typically most have some degree of attic space, either walk-in or crawl space.

Is spray foam insulation in attic worth it?

A properly done spray foam job not only insulates but also greatly reduces the air leakage of a home. But that only works if the installer can get it into the places where most of the air leakage happens. In an attic, the eaves are one of the most critical places to get good coverage with the foam.

What is R 49 insulation used for?

The Owens Corning Paperfaced R49 is a flexible fiberglass insulation proposed to control moisture in concealed applications in between the studs and joists. With a paper facing on one side of the insulation, the R-49 Paperface Batt Insulation is smooth and flexible and can be easily cut for installation.