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Polystyrene Density, Specification & Costing Guide
What you should learn from this guide is that density is important both from a specification perspective but also from a cost perspective.
There are many different products that can do the same thing. Some are more cost effective than others.
You will also from this guide that in certain applications, certain densities must be used, otherwise the product fail and in costriuction applications this is very important to know.
We are here to assist you technically or from a cost saving perspective. Speak to us if you need advice!
Polystyrene Densities
Expanded Polystyrene is manufactured in a low, medium, high and extra high densities. Extruded Polystyrene is manufacture in one density.
Since density affects the physical properties of the polystyrene and cost it is important to understand what densities are most suitable for which construction applications.
Density affects the compressive strength and shear strength of polystyrene which is important when the polystyrene needs to carry weight like in surface bed insulation and raised polystyrene slabs applications.
The higher the density the higher the compressive and shear strength.
Expanded Polystyrene
Densities
Expanded polystyrene is manufactured in many different densities.
This often makes it a very cost effective solution for different applications.
Low Density (X-Grade) - 12 kg/m3
Medium Density - 15 kg/m3
High Density - 20 kg/m3
Highest Density - 24 kg/m3 to 30 kg/m3
Extruded Polystyrene
Densities
Extruded polystyrene is extruded at very high density.
This makes them perfect for thermal ceilings.
Density: 33kg/m3 to 36kg/m3
Expanded Polystyrene Board (EPS) Densities & Properties Table
Surface Bed Insulation
Please Note:
High Density or Highest Density
Polystyrene should be specified and used.
The highest density is the better better option.
Low & Medium densities will cause the slab to fail in this application.
Please be aware that you are unlikely to get this density of polystyrene in your local building store!
Expanded & Extruded Polystyrene Insulation is suitable for this application.
High Or Highest Density Expanded polystyrene PolyFloor Insulation is suitable for this application.
Cavity Wall Insulation
Medium Density Polystyrene Polystyrene is quite suitable for this application.
There is no loading requirement.
Please be aware that you are unlikely to get his type of polystyrene in your local building store!
Expanded & Extruded Polystyrene Insulation is suitable for this application.
Medium Density PolyWall Insulation also suitable for this application.
Concrete Roof Insulation
Please Note:
High Density or Highest Density
Polystyrene should be specified and used.
The highest density is the better option.
Please be aware that you are unlikely to get this density of polystyrene in your local building store!
Expanded & Extruded Polystyrene Insulation is suitable for this application.
PolyRoof High Density & Highest Density Insulation is also suitable for this application.