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WeatherLock™ Mat Waterproofing Underlayment

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WeatherLock™ Mat Waterproofing Underlayment provides outstanding roof deck protection for your home. It helps prevent damage caused by freeze/thaw cycling, wind-driven rains, and normal water flow that occurs around valleys, vents, chimneys and skylights.

Its patented mat-faced design provides a consistent surface, reducing slipping, sticking and scuffing. It is lighter weight than typical granulated products, making it easy to load, carry and install.

Engineered for use with asphalt shingles, wood shakes, and quarry slate roof assemblies. It's an essential part of a Total Protection Roofing System™*.

Thickness 45 mils.
Width 3 ft.
Model Name Area Length

WeatherLock™ M (Mat-Faced) 2 SQ Roll (36 in x 66.7 ft) 200 sq. ft. 66.7 ft.

Applicable Standards

  • ASTM D1970
  • ASTM E108/UL 790 (Class A Fire Resistance)^

The performance of any roof depends on an entire system of Roofing Essentials accessory products and Owens Corning Shingles working and performing together. Below find our shingle recommendations for this product:

* See actual warranty for complete details, limitations and requirements.

^ Underlayment is tested as part of a rood assembly that includes wood decking, underlayment and shingles.

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