Certified Drainage Program

Support and Prolong the Life of Your Roof

The Atlas Roofing Corporation Certified Drainage Program (CDP™ ) is a comprehensive low slope tapered design service led by an Atlas CDP Design Professional who works directly with the Building Owner, Architectural or Engineering Design Professional and Certified CDP Roofing Contractor.

In today’s competitive construction market, tapered polyisocyanurate (polyiso) roof insulation systems are prime targets for so-called “value engineering.” Atlas Roofing Corporation understands that compromises made to tapered roof insulation systems will ultimately lead to premature roof failure. Working directly with an Atlas CDP Design Professional will not only guarantee positive drainage, it will provide a foundation to support and prolong the life of your roof.

The CDP Professional:

  • Will review design intent and develop a tapered system layout to maximize drainage efficiency.
  • Will provide tapered system roof plans for inclusion in the bid documents.
  • Will assist in preparing the tapered roof insulation specifications.
  • Will participate in pre-job meetings.
  • Will examine field conditions prior to material delivery to ensure that as-built conditions match design layout.


Roof examination includes on-site roof measurement, Auto Level Elevation Survey, and identification of potential concerns.

After project completion and 48 hours after a rain event, the CDP Design Team will examine the roof area for ponding water. After acceptance of the tapered roof system by all parties, the CDP Design Professional will issue a Certified Drainage document.

Ponding water is the leading cause of premature roof system failure. Atlas CDP eliminates this problem to prolong the life of your roof.


Roofing Contractor Must:

  • Consult an Atlas CDP Design Professional, who will explain the program in detail.
  • Successfully install a minimum of three Atlas designed Tapered Polyiso Roof Systems with a minimum total of 600 squares of roof area.
  • Schedule an inspection of each project by a CDP Design Professional.


Roofing contractor eligibility requirements to install CDP tapered systems.

  • The #1 reason roof systems prematurely fail is ponding water.
  • One inch of water weighs five pounds per sq. ft.
  • CDP eliminates ponding water and helps prevent:
    • Structural roof collapse
    • Moisture invasion (leaks)
    • Membrane degradation
    • Loss of thermal resistance (LTTR values)
    • Ice formation and resulting roof damage
    • Growth of vegetation
    • Voiding roof system warranty