Roof Flashing Repair Cost Calculator

Pipe boot and vent flashing repairs are the least expensive at $75-$250 because they involve a single penetration point and minimal shingle disturbance. Step flashing along a wall or dormer runs $150-$600 depending on length. Valley flashing repairs cost $200-$800 due to the length of the run and the need to carefully remove and re-lay shingles on both sides. Chimney flashing is the most complex - it involves base flashing, counter-flashing, step flashing, and often a saddle, pushing costs to $400-$2,500 for a full replacement.

Aluminum is the standard residential choice at $0.50-$1.50 per linear foot of material - affordable, rust-resistant, and widely available. Galvanized steel costs similarly but requires paint over time as the zinc coating weathers. Copper is the premium option at $5-$20 per linear foot - it lasts 50+ years, requires no maintenance, and is the correct material for historic homes or slate/tile roofs. Lead flashing is used around chimneys in some older construction and runs $3-$8 per linear foot. Your contractor will typically match the existing material unless you're upgrading.

Low-slope roofs (3:12 or less) are straightforward to walk and work on. Steep roofs (8:12 and above) require harness rigging, toe boards, or scaffolding, adding $50-$300 to the job depending on steepness and height. Multi-story homes with flashing high above the roofline carry additional setup time and safety equipment costs. If your roofer can't safely walk the slope, expect a higher labor quote.

Flashing failures that go undetected for multiple seasons often rot the sheathing beneath. If the contractor pulls back shingles and flashing and finds soft or deteriorated decking, that sheathing must be replaced before new flashing can be installed. A 4x8 sheet of new sheathing plus labor to cut, fit, and fasten it runs $150-$400. Multiple sheets or structural damage to rafters can push repair costs well above $800.

A failed flashing seal can allow water intrusion for months or years before the source is identified. By that time, the attic insulation may be saturated, roof decking may be moldy, and interior ceiling drywall may be stained or bubbled. Interior remediation - replacing insulation, treating mold, patching drywall, and repainting - is a separate cost from the roofing repair itself and can easily run $500-$3,000 depending on how long the leak has been active and how far water has traveled.