Counter Flashing

What This Service Involves

Counter flashing is the upper layer of metal set into a wall or chimney that overlaps the base or step flashing beneath it, shielding the top edge so water cannot get behind the system. In the Pacific Northwest, where rain frequently arrives horizontally on a south or west wind, that overlapping cap is what keeps the vulnerable top edge sealed. We embed counter flashing into a masonry reglet or tuck it beneath siding rather than relying on surface caulk, which our freeze-thaw cycles quickly defeat. This is a common upgrade on chimneys and parapet walls where the original detail was skipped or sealed only with tar. Properly set counter flashing turns a leak-prone junction into a durable, maintainable one.

Benefits

Caps the base flashing so wind-driven rain cannot enter the top edge; Set into masonry or under siding rather than relying on failing caulk; Withstands the freeze-thaw cycles that crack surface sealants; Makes future roof work easier by keeping the wall seal independent; Protects chimneys and parapet walls from persistent moisture intrusion

Our Process

1) Cut or locate a reglet in the masonry, or open the siding above the base flashing; 2) Form counter flashing to overlap the base or step flashing below; 3) Embed the top edge in the reglet or under the cladding and secure it; 4) Seal the reglet and inspect the full overlap for watertightness

What Affects the Cost

Wall material, since cutting a masonry reglet adds labor; Length and height of the counter flashing run; Condition of the base flashing it must overlap; Metal selection and any custom bending required; Access and safety needs on tall chimneys or steep roofs

Best Time of Year

Dry summer and early-fall conditions are ideal, especially when a masonry reglet must be cut and sealed to cure properly.