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.



According to Pliny, aluminium was discovered as early as the days of Emperor Tiberius (14-37 AD). A pure light metal, aluminium has a dull, silvery grey appearance due to the thin layer of oxide that quickly forms in the air. This oxide layer makes it exceptionally resistant to corrosion. 


Overview of properties and advantages:

  • Natural material 
  • Low weight 
  • High stability 
  • Easy to use
  • High elasticity and excellent formability 
  • Cost-effective 
  • Virtually infinite colour options with surface finishing (coating or anodizing) 
  • Complex structures possible through welding, soldering, riveting or adhering 
  • Lowest amount of maintenance needed 
  • Long-lasting and rot-proof 
  • Environmentally friendly 
  • Shatter-proof 
  • 100% recyclable without loss of quality, making it a material with a positive energy balance in the long run 

Melting point: 659 °C
Length variation at 100 K: 2,4 mm/m
Density: 2,70 kg/dm³

Surface weight

Assembly of metals