Aluminum doesn't rust, but the term aluminum rust was often applied by
Kolby & Kolby Window & Door reps to describe the corrosion seen on
some of their aluminum clad window units. If I recall, regarding the
units I saw (worked with them for almost 2 yrs), they concluded
something in the mortar mix or stucco (a particular kind of mortar/
stucco or something put in the mix) was the most likely cause for the
corrosion. I don't know if they had any evidence to prove their
Might have been some kind of fastener, used on those units, too. The
corrosion was not all over, but just in spots on the units I saw.
I don't recall experiencing any other examples of aluminum corrosion.
A good speed square is a must have tool.