What is the average cost to replace roof flashing?

The average cost to replace roof flashing depends on the type and amount of flashing being replaced, but typical ranges provide a useful benchmark. For a small section such as a single vent pipe boot, average cost is 200 to 500 dollars including materials and labor. For step flashing along a 10-foot sidewall section, average cost is 400 to 900 dollars, as it requires removing surrounding shingles, installing new flashing in overlapping layers, and reinstalling shingles. For valley flashing replacement on a typical 20-foot valley, average cost is 500 to 1,200 dollars. Full chimney flashing replacement, which includes both step flashing and counter flashing inserted into mortar joints, is more complex and averages 1,200 to 2,500 dollars. If you are replacing the entire roof, new flashing is normally included in the total roof replacement cost, which averages 10,000 to 20,000 dollars for a typical 2,000 square foot home, with flashing accounting for about 5 to 10 percent of total cost. Material choice affects cost significantly, as copper flashing costs 2 to 3 times more than galvanized steel or aluminum but lasts 50 to 100 years versus 15 to 25 years for galvanized. Labor costs are higher for steep roofs, multi-story homes, and roofs with difficult access. Always ensure estimates include removal of old flashing and proper integration with new shingles.