Standard EPS

Expanded Polystyrene (EPS)

Expanded Polystyrene (EPS), often referred to as Styrofoam, is made from polymer impregnated with a foaming agent which, when exposed to steam, creates a uniform closed cell structure highly resistant to heat flow and moisture penetration.

Expanded Polystyrene is one of the least expensive, most cost effective rigid foamed plastic insulations and is an excellent material for wall insulation applications that come with a restricted budget.

Summary advantages of using Rigid Expended Polystyrene Insulation Foam Panels as an insulated render component are:

  • Permanent insulation for the lifetime of the building
  • Rot proof and durable
  • Lightweight, easy to handle & install
  • Can be cut to fit with a sharp knife
  • Contains flame retardant additive
  • Can be bonded or mechanically fixed to wall


Expanded polystyrene boards are rot-proof and durable and will remain effective for the life of the building; the recommended fixing methods will retain the boards permanently in position. It also has the added advantage of being flood-proof.

Lightweight, easy to handle & install

Expanded polystyrene insulation is easy to cut/ install and there is generally no need for specialised trades or equipment.

Fire Protection

Although the material itself is combustible, when properly installed, the insulation is protected by the cladding or other facing material and should have no adverse effect on either the surface spread of flame rating or the fire resistance of the wall as long as there are no elements of the insulation left exposed. On applications over two storeys, mineral wool fire breaks must be installed at each floor level.


Typical U-value for standard thicknesses EPS board is 0.038W/mK .


Expanded polystyrene has been awarded an A+ rating by the BRE’s Green Guide to Specification.

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