Material properties

GRÖMO manufactures roof drainage accessories in five different materials with nine different surfaces. Only European vendors are used as suppliers. This guarantees high quality in the raw material, and is a prerequisite for the high quality standards of GRÖMO.


Zinc has been used as a component in brass since antiquity. The Europeans discovered the positive qualities of the metal in the 17th century. Thanks to its corrosion resistance, zinc is excellent for roof drainage and is always finding new areas of application - not least because it recycles so well.


Overview of properties and benefits:

  • Natural material 
  • No cleaning or maintenance for a long time because of the material’s self-cleaning nature, thanks to its natural aging and contact with rainwater
  • Becomes more beautiful with age due to natural weathering process 
  • Amazing lifespan due to corrosion resistance and formation of a bonded, non-toxic protective coating under the influence of atmospheric weathering
  • Naturally low erosion
  • UV-resistant
  • Environmentally friendly
  • 100% recyclable 
  • High formability 
  • Easy to handle

Melting point: 420 °C
Length variation at 100 K: 2,2 mm/m
Density: 7,20 kg/dm³

Surface weight

Assembly of metals