How thick is r30 rigid insulation?

Typical R-30 fiberglass insulation is 10-inches-thick. Prior to buying fiberglass insulation, it is important to measure the joint spacing you are working with. Note that the actual space between the framing members will be less than 16 or 24 inches, but the foam batts can easily be stuffed between these lengths.

What does R30 mean on insulation?

A wall is R-19, a roof is R-30 — what does this mean? Essentially R-value is a measure of thermal resistance, or the ability to prevent the transfer of heat. The larger the number, the harder that insulation is working at preventing heat conduction. The less heat loss, the lower your energy bills.

What is the R-value of 2 inch foam board?

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.

Do you need a vapor barrier with rigid foam insulation?

Foam insulation usually does not require a vapor barrier. For some foam insulation types, such as closed-cell spray foam and foam board insulation, the insulation itself stops the movement of most water vapor.

What is the thinnest insulation with the highest R-value?

Aerogel insulation offers the highest R-value of any insulating material at less weight and thickness—ideal for construction, refineries, pipelines, and thin-gap thermal barriers.

Cutting Rigid Insulation

How good is R30 insulation?

R30 insulation can minimize conductive heat loss out of your home by 97 percent, and this will make your home 97% hotter than without insulation, saving you a lot of money on your energy bill.

Is R30 insulation good for walls?

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.

What thickness is rigid insulation?

Rigid board insulation generally comes in standard thicknesses ranging from ½ inch to 2 inches. It is possible for homes located in extreme climates to order specialty thicknesses of up to 6 inches directly from certain manufacturers. Obviously, the thicker the rigid board, the higher the insulation capacities.

What rigid insulation has the highest R-value?

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.

What R-value is 6 inches of insulation?

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.

How much space do you need for R30 insulation?

For future reference, here is the cavity depth you need for some common insulation r-values: 3.5 inches --- R13. 6 inches --- R19. 9 inches --- R30.

How much insulation do I need for R30?

In Zone 1, the average minimum requirement for attic insulation is 9 inches of R30 fill. The average recommended level is 14 inches of R49. In Zone 2, the average minimum requirement for attic insulation is 9 inches of R30 fill.

Can you put r30 insulation in 2x6 ceiling?

If you choose to use the 2x6 roof joists, you'll only be able to "fill" the joist space up about 4.5". So, your choices are 3 1/2" thick batt insulation for an R-value of about R-11.9 or rigid insulation board for a R-20 to R-30, depending on the type of board.

What is the highest R-value for a 2x6 wall?

Fiberglass and rock wool batts—2x4 walls can hold R-13 or R-15 batts; 2x6 walls can have R-19 or R-21 products.

What insulation fits in a 2x8?

Two-by-Eight Floor Joists

According to Peter Ainsworth, fiberglass R-19 batt insulation is about 6 inches thick and is available in 15-inch widths, making it the correct size for insulating a two-by-eight floor joist system.

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.

Is R30 better than R19?

There is a direct relationship between the amount of insulation and the amount of heat transfer. The bigger the R value, the better the insulation is at slowing down the heat transfer. So R19 is better insulation than R13, and R30 is better than R19. The larger the R value, the better the insulation value.

How much insulation is too much?

How Much Insulation is Too Much? In Southern California, you'll want to shoot for an R-Value of around 30 for an optimum experience. The California Department of Energy's 2019 Building Envelope requirements state the minimum R-Value for wood-construction ventilated attic spaces in California is R-22.

What is the R-value of 1/2 inch Styrofoam?

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

What is the R-value of 1 inch spray foam?

Open-cell spray foam has an R-value of 3.7 per inch, while closed-cell spray foam delivers an R-value of up to 6.5 per inch. To achieve the R-value requirements of commercial buildings, spray foam insulation would be a more efficient and optimal choice compared to fiberglass.

What is the R-value of a vacuum?

VIPs have better insulating properties than conventional materials. A one-inch thick vacuum insulated panel can provide an insulating value of R-25 to R-30.