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What is the R-value of 12 inches of blown insulation?

The number is presented per inch, so an R-value of 3.1 at 12 inches would provide an overall value of R-38.

What is the depth of R-38 blown insulation?

To attain an R-value of R38, a depth or thickness of the blown-in insulation of 15,7″ is needed for fiberglass and 11,98″ for cellulose. Cellulose is seen as a more sustainable means of insulation, with the recycled paper being used as insulation.

How thick is an R38 batt?

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 much insulation do I need for an R38 attic?

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

How thick should blown insulation be?

When blown into attics and wall spaces, loose-fill fiberglass offers an average R-2.5 thermal value per inch (the higher the number, the greater the insulating effect). You’d need a thickness of about 7.5 inches of insulation to match the insulating value of a batt of R-19 insulation (R-19 is a common batt value).

What is the R-value of blown in insulation in a 2×4 wall?

Fiberglass and rock wool batts—2×4 walls can hold R-13 or R-15 batts; 2×6 walls can have R-19 or R-21 products.

How many inches is R38 of blown fiberglass?

R-Value Thickness Bags / 1000 Sq Ft
R49 16.25” 22.6
R44 14.75” 20.1
R38 12.75” 16.8
R30 10.25” 13.0
Is R38 insulation good?

In many colder areas of the US, R 18 is the recommended insulation for walls (its a 2×6 wall stuffed with standard fiberglass insulation), R 38 (14 inches of fiberglass) is recommended for ceilings/attics.

How many square feet is a roll of R38 insulation?

A: Hello Pepperpot, One package of Owens Corning R-38 Kraft Faced Insulation Product #ME25 covers 42.67 square feet.

What kind of insulation do you use for a cathedral ceiling?

In general, closed-cell foam is the best choice for unvented cathedral ceilings. It is also one of the most expensive, and most building inspectors will not allow it to be left uncovered (for fire-code reasons). Foil-faced iso-board can be cost-effective insulation for finished attics and cathedral ceilings.

What is the best insulation for Arizona?

Both batted insulation and blown-in insulation may consist of materials such as cotton, cellulose, and fiberglass. Of these materials, fiberglass is often the preferred choice for its ability to cover areas evenly and without settling. Spray foam insulation is made of polyurethane plastic.

What is the cost of blown insulation in an attic?

Blown-In Attic Insulation Costs The cost to insulate an attic with blown-in insulation runs from $600 to $1,200, assuming it is 1,000 square feet in size. If you choose to hire a professional, expect to pay from $40 to $70 an hour for labor in addition to the cost of materials.

Is R38 good for attic?

Every home builder in our area must insulate the attic to a minimum of R-38. … And more insulation generally means your home will be more comfortable, more energy efficient, with a higher resale value.

How do you get R38?

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.

Can you over insulate 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 R-value is 6 inches of insulation?

Fiberglass Insulation Batts Fiberglass blankets or rolls provide an R-value of up to 3.2 per inch, so a 6-inch fiberglass batt may achieve an R-value of 19.2, and some high-performance products are rated at R-21.

Is blown insulation better than rolled?

The Differences Between Blown-in and Rolled Insulation The lower the R-value is, the less effective it will be as insulation – although it will be cheaper as well. … In such situations, blown-in insulation is much more effective since it allows you to easily insulate those hard to reach areas.

How do you calculate blown insulation?

Cellulose blow-in insulation is constructed out of recycled paper. To determine how much cellulose insulation you need, take the square footage of the space and divide it by either the depth or the desired R-value. Fiberglass blow-in insulation is essentially made up of spun fibers from recycled molten glass.

How thick should wall insulation be?

It should normally be at least 60mm thick, and can be up to 100mmm. The actual thickness required will depend on the material used – Insulation boards are fixed straight onto the wall using continuous ribbons of plaster or adhesive.

What is the highest R value for a 2×4 wall?

Cavity insulation, like framing, has options. A 2×4 wall cavity can be insulated from R-13 to roughly R-25. A 2×6 wall can be insulated from R-19 to R-39.

What insulation do you use for 2×4 walls?

Insulation for 2×4 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.

How thick should spray foam insulation be in attic?

Now generically speaking, we usually recommend open cell spray foam to be 6- to 10-inches on a roof deck or ceiling and 3-inches in the walls. Closed cell spray foam should be 4- to 5- inches on the ceiling and 2- to 3-inches in the walls.

How thick can spray foam insulation be?

The ASTM E84 tests for most spray polyurethane foams limit the maximum installed thickness of foams to 4 inches or less. The ASTM E84 tests for some SPF products limit installations to a maximum of only 2 inches.

What is the difference between R38 and r49?

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.

What is r23 insulation used for?

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. 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.

How thick is r21 batt insulation?

5½ ” thick R-21 EcoTouch® insulation delivers 19% more R-value than compressed 6¼ ” R-19 Fiberglas™ insulation. The kraft facing on this insulation will burn and must not be left exposed.

How many square feet does a bag of r38 cover?

Batts (72 sq ft/bag) | InsulationSaver.

How much does r38 insulation cost?

R-valueThickness in inchesPrice range per square footR-3812$0.55-$0.60

What color is r38 insulation?

We recommend R-38 EcoTouch® PINK® FIBERGLAS™ Insulation with PureFiber® Technology for the following projects: Insulating with EcoTouch® PINK® FIBERGLAS™ Batts & Rolls.

Does a cathedral ceiling need a vapor barrier?

Insulating Cathedral Ceilings Sprayed against the underside of the roof deck, it seals against air movement, eliminating the need for a vapor barrier or ventilation. But its open-cell structure still allows moisture to escape.

What R value do I need for vaulted ceiling?

In moderate climates, insulation with R-19 or R-30 thermal values is often sufficient. In colder regions, builders install ceiling insulation with thermal values up to R-49.

What is the difference between a cathedral and a vaulted ceiling?

A vaulted ceiling slopes upward from both sides to form a peak. … On the other hand, cathedral ceilings are defined by their symmetry: they feature two equal sloping sides that meet at a higher point in the middle and often conform to the shape of the roof.

Do I need a vapor barrier in Arizona?

Moisture Control Vapor barriers can actually create problems in wall systems in the desert southwest like Arizona, and are not recommended in these climates.

Should I insulate my garage in Phoenix?

Yes, insulating your garage in Arizona is a must if you want to do anything in your garage for more than 5 minutes without having a heatstroke.

How much insulation do I need in my attic in Arizona?

A: Anywhere below the Mogollon Rim in Arizona, you need to reach at least the R-30 level of insulation in your attic. You can put in a little more fill to reach the R-38 level — which would be slightly better for energy efficiency.

How much does it cost to insulate a 2000 sq ft attic?

How much does it cost to insulate a 2,000 sq ft attic? With average costs ranging from around $1 per sq ft to $5 per sq ft (excluding structural insulation panels as these are best for new installations) expect to pay from $2,000 to $10,000 to insulate a 2,000 sq ft attic.

What type of blown in insulation is best?

Fiberglass, cotton, and mineral wool can all work as loose-fill material, but the far and away top choice for blown-in insulation is fiberglass. Contrary to batts insulation, blown-in fiberglass insulation is perfect for filling in tight voids around wiring, pipes, or any area with awkward framing.

How much does it cost to insulate a 1500 sq ft house?

Property owners should expect to spend about $975 to $11,250 to insulate a 1,500-square foot home. Take note that insulation costs may vary and can increase or decrease, depending on whether the insulation comes during or after the construction of the house.

What is R38 insulation made of?

R-Value Insulation The R-38 fabric is usually a fiberglass or similar material, although it can also be made from cellulose, which is shredded paper that is tightly sealed into the area being insulated.