Over-Foil 311+ – Multilayer Reflective Aluminium Thermal Insulation Sheet
Key advantages
• Multilayer thermal insulation sheet with 7 layers
• Two heat-reflective layers of pure aluminium
• Provides thermal insulation in summer and winter
• Also acts as an effective vapour barrier
• Exceptionally thin – only 14 mm
• Lightweight, flexible and easy to install
• Made from recyclable materials
• Made in Italy to high quality standards
Why this product
Over-Foil 311+ was developed to provide high thermal insulation while keeping thickness to a minimum.
Its multilayer construction with pure aluminium reflects radiant heat and reduces heat transfer in summer and winter, while preserving maximum interior space and reducing transport and storage volume.
Technical description
A reflective thermal insulation sheet made up of 7 layers, including two outer layers of mesh-reinforced pure aluminium, inner reflective layers, padding layers and a foamed PE film.
This construction provides effective thermal insulation, a vapour barrier and reduced cold bridging, while remaining thin and lightweight.
Applications
• Tiled roofs
• Metal roofs
• External and internal walls
• Suspended ceilings
• Attics
• Residential buildings
• Industrial buildings
• Commercial buildings
Technical specifications
Construction:
• 7 layers
Thickness:
• 14 mm
Roll dimensions:
• Width: 1.5 m
• Length: 20 m
• Area: 30 m²
Weight:
• 430 g/m²
Roll weight:
• Approx. 13 kg
Emissivity:
• 0.05
Water vapour resistance factor (μ):
• 90,000
Thermal resistance of the material only (Core):
• R = 0.457 m²K/W
Thermal performance
Wall:
• One layer + one air gap: R = 1.12 m²K/W
• One layer + two air gaps: R = 1.79 m²K/W
Roof:
• One layer + one air gap: R = 0.91 m²K/W
• One layer + two air gaps: R = 1.36 m²K/W
Ceiling above a cold space:
• One layer + one air gap: R = 1.38 m²K/W
• One layer + two air gaps: R = 2.29 m²K/W
Acoustic performance
• Provides some improvement in sound insulation as part of a building system.
• Its main purpose is thermal insulation and radiant heat reflection.
• Where a high level of noise insulation is required, we recommend combining it with dedicated sound insulation materials.
Fire performance
• Reaction-to-fire classification: Class E according to the European standard.
Standards
• UNI EN 22097 – thermal performance and emissivity testing.
• UNI EN 12667 – thermal resistance measurement.
• Reaction to fire: Class E.
• Origin: Made in Italy.
Installation
• Install with an air gap as per the specification for optimum performance.
• Can be installed in walls, roofs and ceilings.
• Make sure the sheets are properly joined to prevent thermal bridges.
• We recommend sealing the joints with dedicated aluminium tape.
• Maintain the continuity of the vapour barrier layer throughout the system.
Sustainability
• Made from recyclable materials.
• High recycled content.
• Significantly lower transport volume than rigid insulation boards.
• Manufactured in Italy using local raw materials to reduce environmental impact.











