Effective attic ventilation is
critical for a long-lasting roof!

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A properly balanced attic ventilation system will help to:

  • Remove excess heat and moisture to protect your roof from premature deterioration
     
  • Prevent roof rot in your attic or roof deck
     
  • Minimize peeling and extend the life of exterior and interior paint
     
  • Limit the growth of harmful mold
     
  • Safeguard your attic possessions against mildew damage
     
  • Guard against ice damming in harsh winter climates
     
  • Possibly reduce excessive heating and air conditioning costs

Cobra® Rigid Vent 2™ exhaust vent is a key part of the GAF-Elk Smart Choice® Roof System Solution, and has even earned the prestigious Good Housekeeping Seal.

Homeowner’s Best Choice

  • Vents Your Attic…
    Allows heat and condensation to escape at the most effective location—the ridge.
     
  • Looks Terrific…
    Shingle-over design blends into your ridge line.
     
  • Watertight…
    Passes the 110 mph wind-driven rain test.*
     
  • Insect Guard…
    Specially-designed louver spacing helps keep insects out.
     
  • Energy Efficient…
    May even reduce your utility bills!
     
  • Durable…
    Designed with high-impact polymers.
     
  • Peace Of Mind…
    Backed by a 40-year ltd. warranty.**

*Under controlled laboratory conditions.

**See ltd. warranty for complete coverage and restrictions.

Professional’s Best Choice

  • Effective…
    Provides 18 sq. inches per linear foot of net free ventilating area.
     
  • Easy Sizing…
    EasyTear™ feature allows you to hand-tear product in 3" increments—no knives necessary and less waste!
     
  • Fits Better…
    Extra-flexible hinge design allows installation on 3:12 to 16:12 sloped roofs.
     
  • No End Caps Needed!
     
  • Crush Resistant…
    Internal structural support for added durability.
     
  • No Gaps…
    Edge overhang allows smooth, continuous coverage between sections.
     
  • Less Call-backs…
    External baffles help deflect wind and rain.
     
  • Cap Shingle Compatible…
    Works with traditional size ridge cap shingles.

Balanced Ventilation Requirements

Balanced ventilation requires an equal amount of intake ventilation and exhaust ventilation. GAF-Elk recommends, at a minimum, providing 1 square foot of Net Free Ventilation for every 300 square feet of attic floor space. Consult local building codes for specific ventilation requirements in your area.

  1. Calculate the total square footage of the attic floor area (round up to the next highest number). This number will determine the minimum total linear feet of Cobra® Rigid Vent 2™ exhaust vent that is needed.
     
  2. Find the appropriate amount of Cobra® Rigid Vent 2™ exhaust vent and minimum intake ventilation that corresponds to the total attic square footage.
Based on 1/300 Rule
Total
Attic Square
Footage
Recommended Length of Cobra® Rigid Vent 2™ Exhaust Vent (Feet)*
Minimum Intake Ventilation (Net Free Area in Sq. In.)
1600
22
396
1900
26
468
2200
30
540
2500
34
612
2800
38
684
3100
42
756
3400
46
828

Cobra® Rigid Vent 2™ exhaust vent has 18.0 sq. in./linear ft. of net free ventilating area.

NOTE: Always have a balanced ventilation system. In no case should the amount of exhaust ventilation at the ridge exceed the amount of soffit ventilation.

Application Instructions

Cobra® Rigid Vent 2™

Application Instructions

 

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Texas Department of Insurance Product Evaluation RV-29

Florida Building Code