How much does it cost to replace flashing on a roof?

The cost to replace flashing on a roof varies widely based on type of flashing, accessibility, and extent of work, but typical ranges can guide budgeting. For small flashing repairs such as replacing vent pipe boot flashing, which is a common leak source, cost is typically 200 to 500 dollars including materials and labor. Replacing step flashing along a sidewall or chimney can cost 500 to 1,500 dollars depending on length and whether shingles need to be removed and reinstalled around it. Replacing valley flashing on a typical 20-foot valley may cost 400 to 1,000 dollars. Full chimney flashing replacement including step flashing and counter flashing often costs 1,000 to 2,500 dollars due to labor-intensive work integrating with brick and shingles. If you are replacing the entire roof, new flashing is usually included in the total roof replacement cost of 10,000 to 20,000 dollars for an average home, with flashing materials accounting for 5 to 10 percent of total cost. Copper flashing costs significantly more than galvanized steel or aluminum, often 2 to 3 times more, but lasts much longer. Costs are higher for steep roofs, multi-story homes, and complex roofs with many penetrations. Always replace flashing when replacing shingles, as reusing old flashing is a major source of future leaks and is considered poor practice. Get written estimates from licensed roofers.