Which foam board 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 foam board?

Foam board insulation R-value varies based on type but is anywhere from 3.6 per inch of insulation thickness to 8.0. The types of foam board insulation include polyurethane, polyisocyanurate, extruded polystyrene foam, and expanded polystyrene foam.

Which rigid board insulating material has the highest R-value per inch?

Among insulation types, rigid foam panels have the highest R-value per inch.

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

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 difference between pink and blue foam board?

Both are manufactured using the same process and contain similar chemical components. The two products also have the same insulating power. However, blue foam boards are manufactured by Dow Chemical Co. whereas the pink foam boards are manufactured by Owens Corning company.

Busting R-value insulation MYTHS

What is the thickest foam board insulation?

The thickest foam board insulation goes up to 6 inches thick, but needs to be custom ordered. Standard thicknesses available for most foam board insulation ranges from 1/4-inch to 2 inches, depending on the type. Obviously, the thicker the foam board insulation, the better it will be at insulating your home.

Which board is best for insulation?

Polyurethane (PUR) is one of the most efficient insulation materials on the market. PUR is available in the shape of insulation boards or foam. However, the boards have a better insulation value than the foam variant. Moreover, these boards guarantee a certain thickness in advance and nothing has to be taped over.

What is the R-value of 2 inch blue STYROFOAM?

A wall utilizing STYROFOAM T-MASS Technology with a 2-inch exterior layer and a 4-inch interior layer of concrete along with a 2-inch layer of STYROFOAM extruded polystyrene insulation would result in a material R-value of approximately 11.33.

What is the thinnest insulation with 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.

What is the difference between Foamular 150 and 250?

FOAMULAR® is a popular energy saving, moisture resistant, XPS insulation from Owens Corning. The difference between 150 and 250 is simply the compressive strength of each type.

What is the most efficient insulation?

Fiberglass insulation still allows for airflow into the attic. Spray foam insulation is the most energy-efficient insulation to create an air barrier in the attic. Certain spray foams can expand up to 100 times its original size, so it fills all of the nooks and crannies in the attic.

What is the R-value of Foamular 250?

(1) “R” per inch: 5.0 (at 75°F mean temperature).

Does rigid foam lose R-value?

A popular rigid insulation choice, XPS features an initial R-value of R-5 per inch. That said, the long term R-values of this foam board decline over time. For example, after just 5 years, an XPS board will see its R-value fall by 10%, and even more going forward.

Does foam board insulation lose its R-value?

Insulation R-value is directly correlated to maximum energy efficiency in a building envelope; higher R-values translate into increased savings. In below grade applications, foam insulation is exposed to moisture and could lose R-value over time if this moisture is absorbed.

How thick should insulation board be?

An uninsulated flat roof has a U-Value of around 1.5 W/m2K. When insulating one, you're aiming for a value of 0.25 W/m2K or less. To achieve this, you should insulate your flat roof with insulation boards totalling around 150mm thickness.

What is the R-value of R Tech InsulFoam?

InsulFoam EPS has R-values that vary depending on temperature and the density of the product installed. For instance, our standard R-TECH, sold in home improvement stores, has an average R-value of about 3.9 per inch at 75°F.

What is the R-value of 1 inch thick STYROFOAM?

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

How thick is r30 insulation?

8¼ ” thick, R-30C EcoTouch® Thermal Batt insulation prevents moisture damage and helps assure long roof life by providing 1" of ventilation air space between the insulation and roof deck. Easy Installation R-30C EcoTouch® Thermal Batt insulation is easy to handle and install.

Does XPS lose R-value?

The trapped gases in the cells of polyiso and XPS foam assist to provide an initial high R-value. During the life of these foams, air from the atmosphere diffuses in and the trapped gases diffuse out. The result is polyiso and XPS lose R-value over their lifetime.

What is the R-value of 6 inch Styrofoam?

One common use of extruded polystyrene foam board is for foundation insulation panels. Polyiso (Polyisocyanurate). This is an even more dense and more expensive foam board insulation. It provides an R-value of 6 per inch of thickness and often comes foil-faced to help reflect radiant heat.

Does foam board insulation need a vapor barrier?

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.