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 R-value of 4 inch of cellulose insulation?

Loose-fill cellulose insulation offers an R-value of around 3.5 per inch of thickness, while densely packed cellulose boasts an R-value between 3.8 and 4.0 per inch.

What is a good R-value for blown in insulation?

R-Value of Insulation by Type

Here are the R-values per inch of the most common types of insulation: Fiberglass (blown): 2.2 – 2.9. Fiberglass (batts): 2.9 – 3.8.

What is the R-value of 2 inches of blown insulation?

Blown-in fiberglass has an R-value of 2.2 to 2.7 per inch.

Can you put too much blown insulation in your attic?

Can you over insulate your attic? The answer is yes! Past a certain point, insulation in a vented attic will do more harm than good. In most of the United States, achieving an R-Value of 38 is more than sufficient.

Insulation R-VALUE - What is R-Value?

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 R-value of 4 inch STYROFOAM?

STYROFOAM extruded polystyrene insulation is rated at an R-value of 5.0 per inch at 75°F.

How many inches is r50 blown insulation?

R 50: Thickness that oscillates between 15 and 19 inches. R 60: Thickness that oscillates between 19 and 22 inches. R 70: Thickness that oscillates between 22 and 25 inches.

How many inches of blown cellulose insulation is r38?

For example, on one manufacturer's coverage chart, to achieve an R-38, the initially installed thickness would be 11.3 inches in depth, which will in turn settle to 10.1 inches. Both mea- surements can be found on a coverage chart.

How many inches of blown insulation is r60?

If you have approximately 6" of existing insulation, you'll need to add an additional 17" to reach R-60. If you have approximately 10" of existing insulation, you'll need to add an additional 13" to reach R-60. If you have no insulation, you'll need 23" to reach R-60.

What is the R-value of 2 inch Styrofoam?

With an R-value of 13.1 for a 2" thick sheet only two 2" sheets are required to achieve R-25. 2. Extruded polystyrene or XPS (foam is usually pink or blue) XPS has an R-value of 5 per inch of thickness requiring 5" of insulation to achieve R-25.

What is the R-value of 6 inches of spray foam?

Spray foam comes in two types, mainly open-cell and closed-cell. Open-cell spray foam has an R-value of around 3.5 per inch. The closed-cell, which is more effective, has a higher R-value ranging between 6 and 6.5 per inch.

What is the R-value of blown cellulose?

The R-value of loose fill cellulose is R-3.2 to 3.8 per inch2. Loose fill fiberglass has an R-value of R-2.2 to 2.7 per inch3. Achieving the desired R-value depends on both the depth of the insulation and its density. Depending on your climate, energy codes require varying R-values for ceiling insulation.

How thick should blown attic insulation be?

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 cellulose insulation be in attic?

Cellulose insulation should be 8-19 inches deep in your attic. Generally, the proper depth of cellulose depends on the following factors: Desired R-value. Insulation density.

What is the R-value of spray foam in a 2x4 wall?

Open-cell spray foam absorbs and holds water. It has a lower R-value per inch than closed-cell foam and is vapor-permeable. The R-value is R-3.5 to R-3.6 per inch, so filling a 2×4 cavity yields about an R-13.

How many inches of insulation is r40?

Fresh, new cellulose loose-fill insulation has an R Value of 3.1 to 3.8 per inch. You see, cellulose insulation has a higher R value per inch than loose fill fiberglass insulation. We are a cellulose installer. To achieve R-40, we install 12” of cellulose insulation.

What is a good 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. 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.

What is the R-value of three quarter inch foam board?

R-5.78 Rigid Foam Insulation.

What is the highest R-value for foam board?

Polyisocyanurate: Known as polyiso for short, polyisocyanurate foam has the highest R-value per inch (R-6.5 to R-6.8) of any rigid insulation.

How do I increase the R-value in my walls?

Achieving Greater R-Values in Exterior Walls

As with attics or anywhere else in your home, adding more layers of insulation to your exterior walls is key to having a higher R-value and better thermal performance. Foam board insulation is easy to install between wall studs and over existing blanket insulation.

What R-value can you get in a 2x6 wall?

Thermal Control

The installed insulation R-value for 2x6 fiberglass batt ranges between R-19 and R-21. When blown or sprayed cellulose insulation is used, the R-value is typically R-20 for 2x6 walls.

How much R-value do you lose when compressing insulation?

For example, standard low-density batts, at their nominal rated thickness — R-11 at 3 1/2 inches, or R-19 at 6 inches — have an R-value of about 3.1 per inch. If you compress a 6-inch R-19 batt into a 3 1/2-inch cavity, you get about R-14, or 4.0 per inch.