52028

Staining on anodized aluminum window frames  

April 30, 2009

I am an Architect in Pennsylvania. A recently completed project is having extensive issues with discoloration of the dark bronze anodized window frames. Of course everyone involved in the process says its not their fault. The staining varies from just a darkening of the metal to a brilliant blue. I believe that it is probably not a metal finishing issues but a contamination from other materials. The staining streaks from the stainless steel flashing above but is also very strong at the sill, where it may be collecting as it runs down the window. The windows are surrounded by silicone sealant and an acrlyic stucco system. Also the stainless steel flashing is sealed with an asphalt based tape behind the stucco system.

Bob Flagg
Architect - Philadelphia, PA, USA