Everything you Know about EPS, XPS and Polyiso insulation 

The three very similar forms of bold insulation used in home construction. An in the building construction industry in general. Today, we’re going to look into how they are made and compared their physical and chemical properties. Let’s start with EPS or Expanded Polystyrene.

What is Expanded Polystyrene (EPS) foam?

The Monomer Styrene is composed of a benzene ring, C6H6 and Ethylene. They’re both made by the petrochemical industry under heat or by an initiator like benzol peroxide. The double bond between the carbon atoms is converted into a single bond. And a polymer chain called polystyrene is formed. This liquid polystyrene is dropped in water to form droplets or beads.

Expanded Polystyrene Insulation is a lightweight, rigid, closed cell insulation. EPS is available in several compressive strengths to withstand load and back-fill forces. This closed-cell structure provides minimal water absorption and low vapor permanence.

Commonly used as insulation for walls, foundations and roofing, there are many benefits to selecting EPS products:

• Long-term R-Value (“R” is the resistance to heat flow)
• Energy efficiency
• Constant thermal resistance
• Measurable energy savings
• Strength

• Sustainability
• No growth of bacteria, nor will it decay over time
• Dimensional stability
• Chemical inertness
• Low cost

A cost efficient, high performing alternative to extruded (XPS) foam, EPS is the perfect choice for many insulation and construction applications.

The Manufacturing Process

These Pictures shows how polystyrene pellets expand in the presence of steam.

 

Commercially, the polystyrene beads are expanded with blowing agents such as propane paint, and methylene chloride.

EPS is created in a two-stage process:

The EPS beads are contained in a mould and then heat or steam is applied to it, which causes the small beads to expand and fuse together. While each individual bead is a closed cell, there is significant open space between the beads. These EPS beads can also be moulded into large sheets or blocks and then cut by Hot-wire machines into thinner sheets or any special shapes or forms.

Currently the available sheet sizes that are used most frequently in local markets are:-

8 ft x 4ft

6 ft x 4 ft

4 ft x 4 ft

The EPS beads are contained in a mould and then heat or steam is applied to it, which causes the small beads to expand and fuse together. While each individual bead is a closed cell, there is significant open space between the beads. These EPS beads can also be moulded into large sheets or blocks and then cut by Hot-wire machines into thinner sheets or any special shapes or forms.

 

EPS is made of 98% air and justice 2% plastic. It can be easily dissolved in acetone and leaves behind barely any residue. This high percentage of trapped air makes it an excellent insulator.

Where EPS is Mainly Used:

It’s widely used in the building construction industry because it’s so versatile.

 

It can be used on roofs, in walls and floors below grade four insulated vinyl siding in insulated concrete forms, or ICF blocks in structurally insulated panels or sips and an exterior insulated finish. Systems are efis. Outside the construction industry, it is used in packaging peanuts, cushioning for fragile items, and disposable food containers.

EPS has many advantages.

  • It has the highest R value per dollar. A four foot by 8 foot by one and sheet at Home Depot cost $16.25. This one in sheet has an R value of about R 3.182 R 4.6 the close cell foam. An air. Also make it an excellent insulator. Visit term in the construction industry called thermal Drift. Which refers to the loss of our value overtime because the air trapped inside the insulation dissipates. The big advantage of EPS is that it has no thermal drift or loss of our value overtime. There’s also no off gassing on site because the blowing agents are trapped. Inside the beads.
  • EPS doesn’t use any CFCs or even HCFCs. A floral carbons are even Kev or hydrochlorofluorocarbons in the blowing process, so it’s the greenest choice among all the three insulation types that we’re going to discuss today since it is impermeable to water, it is mould and mildew resistant. It is also 100% recyclable.