At buildings with flat roof, vertical water draining ducts are installed on certain points of the roof. These are usually made of iron, concrete or hard plastic. Corrosion and the movement of the building may damage these ducts. Their repair is difficult and costly and usually requires decomposition of wall.

An ideal repair method is the RainFlex lining:

In its still soft state, the RainFlex tube is pulled in the damaged rain water draining duct, where being inflated with steam, it takes up the shape of the duct and gets irreversibly hardened thus forming a water and corrosion resistant, composite liner tube with the hardness of steel.


Rain Water


The advantages of RainFlex at repairing rain water draining ducts:
  • does not require any wall destruction
  • no need for removing the old damaged duct
  • perfectly seals the damaged duct even in the capillary cracks
  • installation is completed within a few hours

RainFlex can be applied at vertical rain water draining ducts.

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It is important to have a professionally created inlet form on the roof. The roof insulation needs to be sealed perfectly so that no water can leak underneath.