XPS is manufactured in a continuous extrusion process that produces a closed cell form of foam insulation. EPS, on the other hand, is manufactured by expanding spherical beads in a mold and then using heat and pressure to fuse the beads together. Each product has proponents claiming one out performs the other.

Is EPS and XPS the same?

Extruded polystyrene insulation (XPS) is manufactured using a process of extrusion. … Expanded Polystyrene insulation (EPS) is manufactured using beads of foam within a mould, heat or steam is then applied directly to the beads which causes them to expand and fuse together.

Is Styrofoam EPS or XPS?

As we said, Styrofoam™ is a Dow trade, blue in color, and is an extruded polystyrene (XPS) foam made for thermal insulation, construction and craft applications. EPS is an expanded polystyrene available in various densities for insulation, construction and craft applications and so much more.

What is EPS XPS?

EPS (expanded) and XPS (extruded) are both closed-cell rigid insulation made from the same base polystyrene resins and manufactured differently, EPS is beads that are molded or cut into various sizes and shapes while XPS is extruded sheets.

How good is EPS insulation?

EPS is an extremely durable material Expanded polystyrene will last the lifetime of any building where it’s installed. The thermal performance of EPS does not degrade over time, meaning the U-value you first achieve with EPS will not change.

Is EPS waterproof?

Expanded polystyrene is commonly called beadboard. … While polyiso, XPS and EPS have some of the strongest waterproofing properties of all insulations, EPS is the weakest of the three and absorbs more water. EPS is also susceptible to crumbling on the edges.

Is XPS stronger than EPS?

XPS, at about R-5 per 25 mm, has only a slightly better thermal performance than EPS. … However, EPS with the same level of density is less expensive. XPS is usually avoided in areas where materials with less density are needed or where the material, which is not produced below a certain density, is not applicable.

Is XPS toxic?

Rigid Foam with Flame Retardants Most rigid polystyrene foam insulation boards, both the EPS and XPS types, contain the toxic flame retardant HBCD, which was banned by the European Union in 2015.

Is EPS foam closed cell?

Expanded Polystyrene Insulation, more commonly referred to as EPS, is a closed cell insulation that has been around since the 1950’s. EPS is made of 98% trapped air and only 2% plastic, making it an efficient insulator with a small amount of raw material.

Is XPS fire rated?

There are many listed fire rated wall assemblies that contain Styrofoam™ Brand XPS Insulation or Thermax™ Brand Insulation. The following table lists many of the wall assemblies which contain foam plastics and meet the fire resistance wall requirement.

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Does XPS absorb water?

FOAMULAR® XPS products have an R-value of 5 per inch of thickness, and due to their closed cell structure they resist water absorption, maintaining a high R-value for reliable long term service.

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.

Is EPS insulation fireproof?

Like practically all organic building materials polystyrene foam is combustible. However in practice its burning behaviour depends on the conditions under which it is used, as well as the inherent properties of the material. … When installed correctly, expanded polystyrene products do not present an undue fire hazard.

What is XPS insulation used for?

XPS foam board is often used for above-grade insulation applications such as walls, ceilings, attics and roofs as well as for below-grade applications such as foundations and basements. When used above-grade, it can reduce thermal bridging and improve energy efficiency.

What does XPS mean insulation?

Extruded polystyrene insulation or XPS Insulation is manufactured through an extrusion process. This manufacturing process involves melting together the plastic resin and other ingredients. The liquid formed is then continuously extruded through a die and expands during the cooling process.

Does XPS compress?

What is the compression behaviour of XPS insulation? Among widely available insulation materials, extruded polystyrene (XPS) insulation offers one of the broadest range of compressive strengths and is one of the few products where manufacturers invest the time to test and declare compressive creep.

Is XPS breathable?

Simply put, XPS is not breathable. It retains water over time. This is due to the way it’s produced with the beads being so tightly joined together, resulting in a much lower perm rating than GPS. So, a double vapor barrier is created when a layer of XPS foam board is placed on the exterior of a wall assembly.

Is EPS toxic?

Hygienic and Safe: EPS is non-toxic and chemically inert. Fungi and bacteria cannot grow on it. Waterproof: EPS is insoluble and non-hygroscopic. Low Carbon Impacts: Clean manufacturing technologies mean minimal energy and water inputs with no production waste.

Is EPS the same as Styrofoam?

The foam that you formerly knew as styrofoam is actually expanded polystyrene foam or EPS. This material is made from polystyrene, a plastic that’s often used to make clear products like food packaging or lab equipment.

What happens if EPS gets wet?

What Happens with Expanded Polystyrene Insulation in Contact with Water? … In case of water damage or flooding, don’t worry! EPS is resistant to water and moisture. This means that it does not absorb them and that its insulating performance is not compromised when in contact with these elements.

Is EPS foam breathable?

Rated at R4 per inch; EPS foam insulation boards are more permeable to air and moisture than XPS, but it doesn’t retain moisture to the same extent because of it’s more closed cell structure and it’s breathability which lets it dry out.

What insulation should I use in my basement?

Rigid foam sheets are best for do-it-yourselfers who are insulating basements prior to framing the walls. Rigid foam also works well when the concrete or block walls are smooth and flat. Rigid foam insulation is easy to use.

Is XPS combustible?

While the code requirements for continuous insulation help to improve efficiency, they raise another challenge: the foam plastic insulations commonly used for continuous insulation—polyisocyanurate aka polyiso, expanded polystyrene also known as EPS, extruded polystyrene aka XPS and spray polyurethane foam or SPF—are …

Is XPS mold resistant?

That is a substantial difference to be taken into account when specifying a durable project. The closed-cell structure of XPS makes it more resistant to water. … A higher potential for water absorption means a higher potential for the growth of mold.

Can you paint EPS?

You can paint polystyrene foam or expanded polystyrene beads using a waterborne paint to protect it from solvent attack by subsequent coats of paint. Typical waterborne paints are acrylic or vinyl lattices used for painting building interiors and exteriors or water-soluble industrial paints.

Does EPS insulation off gas?

Ted, There is no off-gassing from EPS. It’s inert, contains no formaldehyde and is non-biodegradable. If it lasts forever in a land fill, it will also last forever in your wall. You may be thinking about the flame retardant, HBCD.

Is burning XPS foam toxic?

To get the polystyrene foams to actually combust and burn you have to have an extremely hot fire, much hotter than our tools get, burning directly on the foam to begin with. … They told us that the fumes from cutting their foam with a hot wire are not toxic, but cutting should still be done in a well-ventilated area.

Is there formaldehyde in spray foam insulation?

RetroFoam injection foam insulation has a trace amount of formaldehyde present in the dry product, but when it is mixed in our trucks, the formaldehyde dissipates. This means the finished foam product installed in your walls is formaldehyde-free. The spray foam products we use contain no formaldehyde at all.

Is EPS non combustible?

However if the heat source is applied continuously the EPS will burn and give off dense and toxic smoke. If EPS has to be used, then the facility should be sprinkler protected. There are now alternatives to EPS that can be considered. These are totally non-combustible panels such as those made from fibre glass ‘wool’.

Is XPS a vapor barrier?

XPS is manufactured in both an unfaced form or with different plastic facings. However, XPS is considered a vapor retarder, not a vapor barrier. … Innovative applications of EPS and XPS have improved a building’s envelope thermal performance.

Is Foamular fire proof?

For roofing applications, use FOAMULAR® THERMAPINK® Extruded Polystyrene (XPS) Insulation. This product is combustible.