Over-Foil Multistrato 27 – Multilayer Reflective Thermal Insulation Membrane
Key advantages
• Multilayer thermal insulation membrane with 27 layers
• Very high thermal insulation in summer and winter
• Heat-reflective pure aluminium in the outer layers
• Built-in vapour barrier
• Also helps reduce airborne noise
• Ideal solution for new construction and renovations
• Made from recyclable materials with a high recycled content
• Made in Italy
Why this product
Over-Foil Multistrato 27 is one of Over-All’s most advanced insulation products.
Its 27-layer structure makes use of the air gaps in the system to deliver very high thermal performance while keeping the system thickness relatively low. It also acts as a vapour barrier and helps reduce airborne noise as part of the building system.
Technical description
A heat-reflective thermal insulation membrane made up of 27 layers, including protected pure aluminium layers and heat-reflective inner layers.
The membrane was developed specifically for dry construction systems, walls, roofs and ceilings, and provides high thermal insulation, a vapour barrier and improved acoustic insulation when combined in a system with air gaps. It has been tested in accordance with UNI EN 22097.
Applications
• Plasterboard walls
• Internal and external walls
• Pitched roofs
• Tiled roofs
• Suspended ceilings
• Floors above cold spaces
• New construction
• Renovations
• Residential buildings
• Commercial and industrial buildings
Technical specifications
Structure:
- 27 layers
- Heat-reflective pure aluminium
Thickness:
- 90 mm
Roll dimensions:
- Width: 150 cm (usable width 147 cm)
- Length: 6.67 m
- Area: 10 m²
Weight:
- 1.4 kg/m²
Roll weight:
- Approx. 14 kg
Emissivity:
- 0.05
Water vapour diffusion resistance factor (μ):
- 90,000
Thermal performance
Thermal resistance of the material alone:
- R = 2.78 m²K/W
In walls
- One air gap: R = 3.44
- Two air gaps: R = 4.11
- Two layers + one air gap: R = 6.22
In roofs
- One air gap: R = 3.23
- Two air gaps: R = 3.69
- Two layers + one air gap: R = 6.01
In ceilings above a cold space
- One air gap: R = 3.70
- Two air gaps: R = 4.62
- Two layers + one air gap: R = 6.48
Acoustic performance
• Helps reduce airborne noise as part of the building system.
• Sound insulation of the product itself:
- Rw = 11 dB.
This value refers to the membrane alone. When it is incorporated into a wall or roof system with air gaps and finishing layers, higher acoustic performance is achieved.
Standards
• UNI EN 22097 – Thermal performance testing of reflective insulation.
• UNI EN 12667 – Measurement of thermal resistance.
• UNI EN ISO 10140-1/2:2021 – Sound insulation testing.
• UNI EN ISO 717-1:2020 – Rating of airborne sound insulation.
• LCA – Life Cycle Assessment.
• Made in Italy.
Installation
• Install with an air gap to achieve maximum thermal performance.
• Suitable for installation in walls, roofs and ceilings in dry construction systems.
• Seal all joints with a suitable aluminium tape.
• Maintaining a continuous vapour barrier across the entire building envelope is recommended.
• Easy to cut and install thanks to the membrane’s flexible structure.
Sustainability
• Made from recyclable materials.
• Contains a high percentage of recycled material.
• Manufactured in Italy from local raw materials.
• Reduces transport volume by a factor of more than 6 compared with rigid insulation boards of similar performance.
• Developed with a focus on sustainable construction and reduced environmental impact.
