A few weeks ago, I shared a true story with you about my failed asphalt shingle roof. If you remember, it had a 30-year warranty, and after just 12 years it began to experience catastrophic failure. Looking back now, I shared the wrong photograph with you. I showed you a picture of my daughter’s new roof with copper strips on it. I should have shown you the photo of the Tilton, New Hampshire, post office roof. That photo accompanies this column.