Universal Dry Valley

Function and compatibility

  • Provides weathertight ventilation in the roof slope
  • Provides up to 10,000mm2 free area of ventilation
  • For natural, mechanical or soil pipe ventilation
  • Can be used with all concrete and clay plain and interlocking tiles
  • Advantages
  • Dry fix, mortar free system for a long maintenance free life
  • Can accommodate up to a 20 degree pitch variance either side of the valley
  • Can be used on pitches up to 60 degree pitches
  • Unique profile maximises discharge rates
  • Gives a finished appearance of a close cut roof
  • Valleys are one of the most vulnerable parts of the roof. Marley Eternit Universal GRP dry valleys provide totally weathertight detailing that are fast and easy to install and compatible with all Marley Eternit concrete, clay plain and interlocking tiles.

    Can be used on valleys up to 8 metres in length

    Accommodates up to a 20° pitch variation either side of the valley

    Continuous support for the valley through must be provided using ply boards

     Rafter pitch

     Max. valley length

     Min. lap length

     15 to 17°

     10.0m

    400mm 

     17.5 to 22.5°

     12.0m

    350mm

     22.5 to 29°

     14.5m

    300mm

     30 to 34°

     15.0m

    250mm 

     35 to 39°

     15.5m

    200mm

     40 to 44°

     16.5m

    150mm 

     45 to 49°

     17.5m

    150mm 

     50 to 55°

     18.5m

    150mm 

    This table is a guide to the recommended application criteria. It assumes a standard roof intersection of 90° and a roof drainage area of 100m². For applications other than this, specific advice should be sought from our technical department.



    Here at Marley Eternit, we are always on hand to offer practical and experienced support.