The Problems

Advancements in asphalt shingles enables them to last longer today than ever before. One problem that can call for premature shingle replacement is the underlayment. The average felt underlayment has the potential to absorb moisture, which can damage the roof deck. Subsequently, moisture can cause the underlayment to swell, which can telegraph to the shingles, creating a roof that appears warped or wrinkled.

Over time, roofing felts can become brittle and more prone to cracking and failure before the shingles need to be replaced. Roofing felts are also weaker than high-performance underlayments and can easily be damaged during installation as roofers walk on the unprotected felts. 

The Solution

A high-performance roof underlayment will add extra protection and value to your asphalt shingled roof.

DELTA®-ROOF is designed to provide ultimate protection to ventilated pitched roofs. Tough, waterproof, and wind resistant, DELTA®-ROOF is designed to help asphalt shingles last the life of the warranty and beyond.  

Product Details
Product Benefits
  • 4-layer roof underlayment
  • Outer layers are made from a spun-bonded polypropylene
  • Inner layers comprise a waterproof polymer layer and reinforcement grid  
  • Low vapor permeability helps to prevent buckling of shingles caused by solar-driven moisture that could cause the sheeting boards to swell and expand
  • Waterproof, providing superior protection to the roof against wind-driven rainwater and snow
  • Tough material, more resilient than conventional asphalt-saturated base sheet
  • Strong reinforcement mesh makes this underlayment extremely tear resistant, even when exposed to high winds
  • Surface texture provides high abrasion resistance, preventing slipping during installation
  • Lightweight, easy to install
  • Available in rolls 4'11" (1.5 m) wide by 164’ (50 m) long 

Guide Specifications

Installation Guides

Product Details

Technical Data

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