Polytex® 145 AG – Waterproof yet Breathable Thermo-Reflective Membrane
Key advantages
• Waterproof and resistant to rain penetration
• High water vapour permeability (breathable membrane)
• Reflects up to 97% of radiant heat
• Improves thermal insulation when combined with an air gap
• Reduces heat build-up in summer
• High tear and tensile strength
• Lightweight, flexible and easy to install
• Made in Italy
Why this product
Polytex® 145 AG combines three functions in one product: waterproofing, controlled water vapour transmission and radiant heat reflection.
When installed with a 20–40 mm air gap, it significantly improves the thermal insulation of walls and roofs, helps prevent the building from overheating in summer and keeps the building envelope dry and breathable.
Technical description
A thermo-reflective membrane made of polypropylene (PP), coated on one side with micro-perforated pure aluminium.
The aluminium has an exceptionally low emissivity of 0.02, allowing it to reflect up to 97% of infrared radiation. The membrane is waterproof yet permeable to water vapour, and therefore helps keep the building envelope dry and ventilated.
Applications
• Tiled roofs
• Metal roofs
• External walls
• Timber-frame walls
• Light steel structures
• Ventilated facade cladding
• Residential buildings
• Commercial and industrial buildings
Technical specifications
Material:
- Polypropylene (PP) with pure aluminium coating
Colour:
- Grey / aluminium
Thickness:
- 0.75 mm
Roll dimensions:
- Width: 1.50 m
- Length: 50 m
- Area: 75 m²
Roll weight:
- 10 kg
Mass per unit area:
- 143 g/m²
Density:
- 190 kg/m³
Thermal conductivity:
- 0.22 W/mK
Specific heat capacity:
- 1700 J/kgK
Sd value:
- ≤ 0.18 m
Water vapour resistance factor (μ):
- 24
Thermal performance
• Reflects up to 97% of radiant heat.
• Emissivity:
- 0.02 before ageing.
- 0.03 after artificial ageing.
• Significantly improves thermal insulation when installed with a 20–40 mm air gap.
Waterproofing performance
• Watertightness: Class W1
• Water column:
- Over 200 cm
• High water vapour permeability:
- 120 g/m²/24h
• A breathable membrane suitable for building envelopes.
Acoustic performance
• This product is not intended for sound insulation.
• Its main purpose is waterproofing, breathability and radiant heat reflection.
• It can be combined with acoustic insulation materials as part of a wall or roof system.
Fire performance
• Reaction to fire classification:
Class E.
Standards
• Watertightness class:
W1
• Reaction to fire classification:
Class E
• Country of origin:
Made in Italy
Installation
• Install with the aluminium side facing the air gap.
• Leave an air gap of 20–40 mm for maximum thermal performance.
• Fix with staples or nails.
• Overlap the sheets by 15–20 cm.
• Seal all joints with dedicated aluminium tape.
• Suitable for installation on both rigid and soft substrates.
