In almost all cases, we replace flashing during a reroof to ensure a watertight system and preserve manufacturer warranty coverage.
What we replace
- Step & counterflashing (sidewalls): New step flashing under each shingle course; new counterflashing let into a masonry reglet or behind siding—not face-caulked.
- Headwall/apron flashing (where roof meets wall): New continuous apron with properly lapped underlayment.
- Chimney flashing system: New step + counterflashing set into mortar joints; we add a cricket on wide chimneys to divert water.
- Valley metal (if specified): Open W-valley or closed-cut per your system; metals matched to shingle manufacturer guidance.
- Drip edge & gutter apron: New metal at eaves and rakes for edge protection and clean water shed.
- Kick-out (diverter) flashing: Installed at the base of sidewalls to prevent wall rot—often missing on older roofs.
- Skylight flashing kits & pipe boots: New manufacturer kits/boots; never reusing brittle rubber.
Materials & methods
- We use manufacturer-approved metals (aluminum, galvanized, or copper as specified) and compatible fasteners/sealants to avoid corrosion or warranty conflicts. Flashing is integrated under the shingles and over the water-resistive layers in the correct shingle-style laps. Sealant is used only as a complement—never as a substitute—for proper metal detailing. Where visible, we color-match exposed metals when practical.
When reuse is considered (rare)
- Only if the existing flashing is truly new, undamaged, code-compliant, and fully compatible with the new roof system (including warranty). If reuse makes sense—e.g., recently replaced copper at a historic chimney—we’ll review the tradeoffs, get your approval in writing, and document the condition with photos.
Documentation & quality control
- Flashing locations and types are shown on your proposal diagram.
- We photo-document hidden areas during install and at completion so you can see every critical detail.
- Any inspector comments or punch-list items are corrected promptly at no added cost for items within our scope.
Bottom line: new, properly integrated flashing is the backbone of a leak-free roof. We replace it as standard practice and only reuse in exceptional, documented cases.