Optima -42 mm
High performance
thin insulation



A reflective insulation material made thicker to comply with European standards.

Mainly used on roofs and walls as insulating vapour barrier.

EPC & LABC certified.

How does Optima®  work ?

OPTIMA is composed of the following compressible successive layers:

  1. A film of pure 30 microns thick aluminium, treated against oxidation
  2. A layer of bubbles of dry air enclosed in polyethylene
  3. A moisture-proof polyester fiber
  4. of dry air enclosed in polyethylene
  5. A layer of bubbles of dry air enclosed in polyethylene
  6. A film of pure 30 microns thick aluminium, treated against oxidation

aluthermo optima

The aluminium sheets reflect thermal radiation summer and winter, while the polyester wadding core and the dry, stable air trapped in the bubble film effectively slow the transfer of energy by conduction.
This thin, high-performance insulation material also offers an impermeable barrier to moisture and is vapour proof.



  • EPC & LABC certified
  • Insulation and vapour barrier all in one
  • Easy to install as it is welded across its entire surface
  • Multi-reflective and multi-layer with a reinforced thermal and acoustic performance
  • Reduces thermal bridges
  • Durable as pure aluminium
  • 10-year warranty in association with Allianz Assurances


Technical characteristics


Dimensions of the roll 1,20 x 15 m (± 2%)
Surface area per roll 18 m²
Weight ± 1100 g/m²
Thickness ± 42 mm
Operating temperature range -55°C à +80°C
Fire resistance classification F
Thermal core resistance R = 1,07 m².K/W (EN 12667)
Thermal resistance in horizontal flux R = 2,37 m².K/W (EN 16012) (*)
U = 0,42 m².K/W (EN 16012) (*)
Thermal conductivity λ = 0,039 W/(m.K) (EN 12667)
Thermal performance Up to 29% more effective than 200 mm of mineral wool (*)(**)
Emissivity < 0,05 (EN 16012)
Acoustic attenuation Rw (C ; Ctr) = 41 (-5 ; -13) dB
Sd value > 6000 m
Thickness of the polyethylene film 150 microns
Number of the aluminium films 2
Thickness of the polyester fiber ± 37 mm
Thickness of the outer aluminium film  30 microns

(*) Performance data only valid for the installation between 2 air gaps without direct contact (see installation instructions of the product).
(**) Thermal performance measured by the Eliosys laboratory, comparing the energy consumption of a structure insulated once with Aluthermo and once with 200 mm of mineral wool (λ 0.040 W/m.K.).
In the absence of consensus on the standard, this result is not considered in the calculation of the EPC or the obtaining of a subsidy. See the Eliosys test report.

Applications of l’Aluthermo® Optima

Meeting with Jan Van Dorpe, Carpenter in Oudenarde

See how it uses Optima Thin Insulation.

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