I have Cedar Shake Siding stained a dark oxford or chocolate brown. When house was about 20 years old, I had it sealed with an Oil based Primer, then stained a Juniper Blue with a Latex stain. Seven years later, it was in need of a spruce up due to some blistering and peeling and limited mildew damage. I cleaned the mildew areas with a special mildew killer, sc****d re-sealed with a good quality Primer and applied the same Stain after adding some mold inhibitor to it. In less than a year it is peeling right down to the original Cedar shake BIG TIME! What did I do wrong? How should I re-do this for a more permanent solution? The original coating lasted for about 7 years. Mine lasted about 7 months.