Explore our brands

Need some help with our products or can't find what you're looking for ?

Contact Us
Back to product listing

Duo Window Membrane HD

ME501 is a high strength, tear resistant membrane made from polyethylene copolymer film with non-woven fabric. It can be applied before or after window installation to suit on-site details and programming. It is also available with gasket options for fixing to window profiles.


ME501 provides a high performance seal to the perimeter joint between the window/curtain wall and the construction reveal. Due to the intelligent, variable vapour permeability (sd value), when used in an internal UK (warm) environment, it will be vapour-tight, and when used in an external UK (cold) environment it will be vapour open. This means that the membrane is suitable for interior and exterior use providing an air-tight and weather-tight seal whilst always complying with inside tighter than outside principles.

  • Complies with principle of ‘inside tighter than outside’ in order to facilitate efficient vapour control
  • BBA accredited alternative to EPDM in many applications
  • Excellent drying potential (due to the membrane’s vapour permeability) avoiding mould growth and physical damage
  • UV stable  - will tolerate up to 9 months direct exposure prior to covering
  • Fully compatible with illbruck building protection membranes

Technical data



Test Method


Building Material Class

DIN 4102

B2 (ABP P-NDS04-776)

Water Vapour Permeability

EN ISO 12572

sd value between 0.3 and 20 m, depending on average atmospheric humidity, and acts as an intelligent vapour barrier

Water Vapour Resistance Factor (µ)

DIN 52615

500 - 33000

Weathertight Against Driving Rain

EN 1027

> 600 Pa


DIN 18542
EN 1026

< 0.1 m3/[h m (daPa)n]

Adhesion of the Self-Adhesive

AFERA 4001 P11

minimum 12 N/25 mm

Compatibility with Traditional Building Materials in Contact

DIN 18542


UV Resistance of the Non-Woven Film Composite (Non-Woven Composite, Weathered Fleece Side Free)

12 months

Temperature Resistance

-40°C to +80°C

Processing Temperature 

+5°C to +45°C

Storage Period 

1 year