The Problems

Unlike asphalt shingle roofs, which are nailed tight to the underlayment, tile and slate roofs allow air and moisture vapor to flow beneath them.

The Solution

Using a high-performance underlayment will allow moisture from within an unvented or highly insulated structure to diffuse outward into the ventilated space, preventing moisture accumulation.

DELTA®-FOXX is the highest vapor permeable, water-resistive underlayment on the market today. It is a 2-layer roof underlayment, specifically designed for use with tile and slate roofs.

Product Details
Product Benefits
  • 2-layer roof underlayment
  • Water-repellent dispersion coating
  • Composed of special polyester non-woven substrate
  • Class A fire rated
  • Watertight, resisting the passage of bulk water from wind-driven rain and snow
  • Tough, waterproof, and wind resistant, keeping insulation dry and functional
  • Ideal for long-term roofs to help prevent an expensive, premature replacement
  • Very high water vapor permeability, ensuring excess moisture is quickly removed from the roof
  • Lightweight, easily lined up and unrolled, making application more efficient and reducing costs
  • Does not distort or buckle
  • Smooth underside of the product allows it to be effortlessly pulled over rough-sawn surfaces
  • Anti-glare coating prevents annoying reflections even in extreme sunlight
  • Extremely tear and scuff resistant, making walking on it – wet or dry – firm and safe underfoot


Guide Specifications

Installation Guides

Product Details

Safety Data Sheets

Technical Data

Related Accessories



    Use DELTA®-FLEXX-BAND tape to seal internal and external building elements. A stretchable, effective adhesive that works in a range of temperatures.


    DELTA®-MULTI BAND is a versatile tape with very strong adhesion. It is highly resistant to aging, and suitable for internal and external use. Composed of pure acrylic adhesive, the product is extremely flexible.