Pry, chisel and scrape off old metal flashings and roofing cement. Before you do anything, get your ladder, roof brackets and safety harness set up so you can work safely and efficiently on the roof.

Flashing is a good way of preventing water from entering a dwelling at the point where the roof meets the walls. To begin the installation, fold a five-by-seven piece of aluminum flashing lengthwise.

Q. I had a home built this year and decided to have it inspected. The inspector found a problem with the “counter flashings,” which he said were improperly installed. The metal flashings are on the ...