Modified Roofing Systems

Modified roofing systems come in various options for material thicknesses, finishes and number of plies. It can be cold-applied, installed with hot asphalt, or heat-welded with propane flame. The top layer is called the “Cap Sheet” and can be covered with granules or gravel, or be smooth with a liquid coating.   This allows for a wide selection of finished colors, especially when acrylic coatings are applied. Modified systems are often found on hospitals, automotive plants, data centers and universities.

Kalkreuth Roofing can assist in determining the type of modified system best suited for your situation. We can also install both self-adhered and fully-adhered vapor barriers under any of our roofing systems.

Modified Bituminous Roofing Systems

Modified bituminous roofing systems could be considered the “modern” version of the old tried-and-true asphalt built-up systems.   Multiple plies, or layers, are applied with adhesives to achieve a highly durable roof assembly. Typically asphalt based, modified systems may also be based on coal-tar composition. The most popular systems are SBS and APP, which consist of asphalt and other chemicals combined for flexibility and durability. Warranties are available from 10 to 30 years.


  • Highly Durable – multiple plies/layers of material in adhesives
  • Wide variety of standard finish textures and colors
  • Can be phased on new-construction projects so that the top layer is the final stage


  • Asphalt or Coal-tar
  • Various thicknesses and strengths of plies
  • Granules, gravel or smooth finish
  • Multiple color options depending on type of finish


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Single Ply

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