The Problems

A key challenge with many interior vapor barriers – such as polyethylene – is that, even with a careful installation, it is almost impossible to prevent some moisture vapor from entering the wall cavity.

Every staple, seam or wall intrusion creates an opportunity for moisture to get past the vapor barrier and into the wall cavity. This can lead to mold, moisture damage, and a reduction in the performance of the insulation.  

The Solution

To protect the wall cavity and insulation from these problems, a high-performance barrier that is impermeable to water vapor is the best solution.

DELTA®-REFLEX is completely impermeable to water vapor. This highly effective barrier helps to prevent wetting and damage of thermal insulation, protecting the building enclosure for many years to come.  

Product Details
Product Benefits
  • 4-ply membrane
  • Highly reflective and corrosion-resistant aluminum layer laminated between a transparent polyester film and a grid-reinforced polyethylene film
  • Fire rating (B1 - DIN 4102) 
  • Completely impermeable to water vapor; helps to prevent wetting and damage of thermal insulation
  • If installed as a radiant barrier, the aluminum layer enhances the effectiveness of thermal insulation by up to 10%. Another benefit is 50% heat reflectance, allowing for a more energy-efficient structure
  • Shields off up to 99% of hazardous electromagnetic radiation
  • Can be installed explicitly as a radiant barrier – there simply needs to be a 1” space between DELTA®-REFLEX and the drywall
  • Extraordinary tensile strength; prevents tearing during installation
  • Extreme flexibility allows for quick installation, even in difficult places 

Product Details

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