NBS Source
List your products

This product is no longer available


ICB (International Construction Bureau) Limited Alwitra rainwater outlets and accessories are designed for use with ICB's EVALON® or EVALASTIC® single layer roofing systems. They are available in both vertical and horizontal forms.

Features and benefits:

  • Adapted to the specific requirements for rainwater and emergency outlets for low slope roofs.
  • Provides high discharge rate and a low ponding height.
  • Manufactured from highly impact resistant polypropylene (PP).
  • Various combination possibilities are available.
  • Tested according to DIN EN 1253.

General information
Specification data - Gravity rainwater outlets
Product Reference

Alwitra Rainwater Outlet


Horizontal DN70/ DN100/ DN125

Refurbishment Vertical DN70/ DN100/ DN125

Vertical DN70/ DN100/ DN125/ DN150

Waterspout S DN50/ DN70/ DN100

Waterspout SF DN50/ DN70/ DN100

Waterspout SW DN50/ DN70/ DN100

Waterspout SF Rectangular 100/ 300/ 100/ 500

Waterspout SW Rectangular 100/300/ 100/500





Leaf Guard

Terrace Grate


Not required

Flexible bellows connector

Heating element

Reducer, 100 to 70 mm

Reducer, 125 to 70 mm

Reducer, 125 to 100 mm

Product Options


- Vertical/ Horizontal:

  • Vertical: S 125/ 110 and SH 125/ 110 for DN 125 and DN 100.
  • Horizontal: W 75/ 110 and WH 75/ 110 for DN 70 and DN 100 as well as W 125 and WH 125 for DN 125).

Provides the connection between drainage pipes and the water-proofing at cold or inverted roofs.

- Refurbishment Vertical:

For use in the case of refurbishment with additional thermal insulation, where it is not possible to replace existing outlets. Uses the custom-fit refurbishment plate (DN 125 made of PP, DN 100 and DN 70 made of aluminium), which is flashed against the existing waterproofing without back flow. Flashing against the new waterproofing is carried out either with connecting flange and screw ring (refurbishment rainwater outlet 125) or with factory-fitted connecting flange (refurbishment rainwater outlet 75, 110).

- Waterspouts:

Part of the roof and emergency drainage system for non-used or extensive green roof areas covered with EVALON® waterproofing membranes. They can be installed horizontally through the para-pet. Made of rigid polyvinyl chloride (PVC) and, depending on the version, are equipped either with a welding flange for EVALON® waterproofing membranes or with a factory-fitted connecting flange made of EVALON®. Along with the waterspouts for pipes with various diameters, rectangular versions are also available. These rectangular water spouts feature high discharge rates at low ponding heights.


EVALON® or EVALASTIC® flexible flange for connecting to EVALON® or EVALASTIC® single layer roof coverings.


  • Flexible bellows connectors: Neoprene rubber for use on lightweight roofs subject to movement and vibration caused by wind pressure and suction, plant, etc.
  • Heating element: 24 volt system to prevent freezing.