Help the gutters are corroding too much

[HasseHunna]

Installed new aluminum gutters last summer. For some reason, they have corroded a lot. I can't figure out why. I used aluminum screws. Does anyone know more about corrosion and how aluminum reacts with other materials?

/Hasse

 

[Pucco]

Aluminium corrodes in an alkaline environment. It is unsuitable in conjunction with concrete and lime.

 

[HasseHunna]

Thanks for the answer. However, there is nothing made of concrete or lime near the gutters. The house has a wooden facade and a lacquered sheet metal roof.