These were typical on many system built properties from the 60's, and
the problems that we have to deal with today are water penetration due
to rotten/punctured/defective sarking felt at the eaves, and also
problems with gutter leaks or overflowing.

This causes water to soak backwards into the wall, where otherwise it
would drip from a soffit.

This design requires carefull detailing and care should be exercised
when constructing.

dg