What Is The R Value Of 1 Inch Styrofoam?

What insulation has the highest R value per inch?

R-value (insulation)Vacuum insulated panels have the highest R-value, approximately R-45 (in U.S.

units) per inch; aerogel has the next highest R-value (about R-10 to R-30 per inch), followed by polyurethane (PUR) and phenolic foam insulations with R-7 per inch.

Straw bales perform at about R-1.5 per inch.More items….

What is the R value of 3 4 Styrofoam?


Which side of foam board insulation faces out?

If you’re wondering whether to put the foil side of foam insulation board shiny side in or out, consider whether you want to make the space inside warmer or cooler. If you want to make the space warmer, the foil should face inside so it can reflect radiant heat back into the room.

What is the best Styrofoam insulation?

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. This type of rigid foam usually comes with a reflective foil facing on both sides, so it can also serve as a radiant barrier.

Does pink foam absorb water?

Yes pink and blue board are closed cell foam boards and will not absorb moisture.

How thick should insulation be?

about 10 to 14 inchesThe higher the R-Value, the better the thermal performance of the insulation. The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.

How thick is r38 rigid insulation?

It comes in standard-size 4×8 sheets, and smaller sizes, in many different thicknesses from 1/4 inch to 2 inches.

What is the R value of 4 inch Styrofoam?

Expanded Polystyrene Foam This product typically has an R value of 3.6 to 4.0 per inch of thickness.

Do you need a vapor barrier with foam board insulation?

Rigid foam insulation is it’s own vapour barrier in this application, so you don’t need to use the poly. Just make sure you tuck tape all the joints. … Yes, you can go right over your existing blown in insulation with batt insulation, just make sure you butt the batts up tight against one another so there are no gaps.

Does rigid foam insulation need to be covered?

Rigid foam insulation, whether it is expanded or extruded polystyrene, does have to be covered if it is installed in the interior of a building. This wall covering must have a minimum fire rating to protect the insulation from quick combustion during a fire.

What is the difference between Styrofoam and foam board?

The major difference between Styrofoam and EPS foam blocks is that Styrofoam is made from extruded polystyrene (XPS) while EPS foam blocks are made of expanded polystyrene. … Both are polystyrene foam products made from polystyrene resins but they are manufactured into sheets and blocks very differently.

How thick is r25 rigid insulation?

2-inchDevelop a 2-inch thick composite foam insulation board with R25 (hr-ft2-F/Btu), with a cost premium of $0.30/ft2.

What is the R value of Styrofoam?

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

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.

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 6 inch Styrofoam?

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.

Can you leave foam board insulation exposed?

Q: Can FOAMULAR® be left exposed in interior applications? A: No. To comply with building codes, all foam plastics must be covered with a 15 minute thermal barrier.

Is Styrofoam good for insulation?

Styrofoam has millions of small air bubbles trapped inside the foam. Since air is a bad conductor of heat Styrofoam efficiently prevents heat transfer. … Styrofoam reduces conduction and convection. In this way, it is one of the best existing insulators.