Insulation on the basis of extruded polystyrene is one of the standard and most widely used leveling underlays employed under floating floors.
STARLON Insulation
STARLON Insulation

Therefore, a composition containing exactly these extruded polystyrene underlays was submitted for the certification of ECOFILM heating foils at the Norwegian NEMKO certification institute. It is not mandatory to use these underlays when installing and operating ECOFILM heating foils; however, FENIX recommends this solution because it corresponds to the certified composition.

STARLON insulation is supplied in two thicknesses – 3 and 6 mm. The thicker insulation provides better thermal insulation and makes it easier to place the floor probe of a thermostat, the connecting conductors as well as the foil connectors into it; however, it also increases the thickness of the structure. Check with the supplier of the floating floor that the thickness of the leveling underlay is not delimited in the installation rules.

Sectional view of floating floor with insulation STARLON
STARLON Insulation
STARLON Insulation
STARLON Insulation
STARLON Insulation


Type Thickness Bulk density Thermal conductivity coefficient Load resistance Dimensions Packaging Cat. No.
[mm] [kg/m²] [FW/mK] [t/m²] [m] [m²]
STARLON 3 3 40 0.0315 5.2 0.5x1.0 boards 5.0 5442032
STARLON 6 6 33 0.0298 6.7 0.5x1.0 boards 5.0 5442034

PE foil

Type Thickness Dimensions Packaging Cat. No.
[mm] [m] [m²]
PE foil 250µm 0.25 1.2x10 12 6651030