Extruded polystyrene (XPS) and Expanded polystyrene (EPS) are thermoplastic polymers made using polystyrene. The major difference lies in the way the two materials are manufactured. XPS uses an extrusion process where additives and resin are extruded through a die. Then it cools and expands to its final form. EPS is manufactured by feeding tiny polystyrene balls into a mold and heating the mold to fuse all the beads. 

Properties And How Are They Different

XPS

Extruded polystyrene foam is resistant to moisture, a long list of chemicals, and several other detrimental factors. Anyways, a few resins, toluene, and acetone can affect XPS. The material’s closed cell structure keeps water absorption minimum and doesn’t let water affect anything beyond the sheet’s outer sides. 

The cell structure and low water absorption characteristics help the foam withstand repeated freezing. It has low thermal conductivity and excellent noise-absorbing properties too. That’s the reason behind its widely being used as an insulation material. 

The material’s low vapor permeability makes it ideal protection against precipitation and groundwater. Thus, any structure that is densely insulated using XPS will require well-planned ventilation structures. 

A major drawback of XPS is its flammability. It is grouped as slightly flammable and does not emit harmful substances during combustion. Some compositions of the material are made with fire-retardant additives. 

EPS

Expanded polystyrene is good at thermal insulation because of its fire-retardant properties. Even if exposed to fire, it does not emit thick smoke and is easily extinguished. Also, it is highly resistant to impact and pressure and good at absorbing shocks.  

Similar to XPS, the material is highly waterproof and resistant to moisture. You can cut and mold the material into shapes that suit your requirement. The cost per unit volume is low, much like the material’s density. 

Although low in density, the material has a very high stiffness that makes parts manufactured using EPS highly durable yet lightweight. When used in construction, it is resistant to events like earthquakes since it reduces a building’s dead load. Also, it does not break when the building is exposed to an earthquake. 

How They Are Different

Although made from the same raw material, XPS and EPS are vastly different materials because of the methods used to manufacture them. In addition, EPS has lower environmentally harmful effects compared to XPS. 

Common Areas Where They Are Applied

EPS In Construction

The thermal, longevity and floating properties of EPS make it an excellent construction material. Architects and developers agree upon the fact that EPS makes constructed structures sturdy and long-lasting. 

Here’s a list of applications of EPS in the construction industry,

• Exterior Finishing
• Floatation devices
• Geofoam & landscaping
• Insulated panels
• Marine
• Parapet Mold
• Pontoons
• Raised Floor
• System EIFS
• Thermal Insulation
• Void Fill
• Void Form

EPS In The HVAC Industry

The thermal properties of EPS lend well to HVAC equipment like ducts and pipe insulation. It keeps heat loss low and helps maintain the temperature in fridges, coolers, chillers, etc. 

EPS In Packaging 

The foam is good at keeping fragile items safe during transit. Its light weight makes it more suitable as a packaging material. Since EPS is versatile, it can be molded in any shape and size possible. 

Some applications include, 

• Appliance and electronics packaging
• Perishable goods transportation
• Temperature regulated packaging

XPS In Construction

XPS is a versatile material commonly used in various construction applications, mostly as foam board insulation. The major application of XPS is wall and roof insulation, thanks to its ability to adapt to adverse weather conditions. Also, it offers the best value for money and can be used on roofs, walls, and floors. 

Another interesting benefit of using XPS in building insulation is its efficiency helps reduce energy usage. 

XPS In The HVAC Industry

Like EPS, XPS has excellent thermal properties, making it an apt choice for HVAC applications. XPS is extensively used in cold storage solutions and cool rooms where it is required to lower and sustain temperature.

XPS In Modeling

The closed-cell structure of extruded polystyrene makes it an excellent raw material for building crafts and models, especially architectural models. It lends well to cutting and reshaping and is lightweight and easy to transport. 

XPS Over Cardboard

Because of the way it’s manufactured, XPS does not need facers to retain its physical and thermal properties. So, it is an excellent alternative to corrugated cardboard. 

If you are still confused about choosing the right product for your project, get in touch with us. Our Industry leading experts will help you draw the comparison personalized to your needs to help you with the decision.