Dry Rot Under Tyvek with Cedar Shingle Siding

complete dryrot on sw wall -- quite literally hanging by the staples in the TYVEK.  wind blows.  sand penetrates siding and Tyvek.  sand stays trapped behind Tyvek because Tyvek reacts with natural Cedar oils.  sand attracts moisture.  termites move in.  moisture ants move in next.  plywood delams and loses shear strength.  Lesson:  only use tar paper at the beach. mission accomplished by Sam Greenwood.