Chimney Flashing Replacement Cost

Greater Victoria has more brick chimneys per street than almost anywhere in BC because so much of the housing predates 1950 and was built with coal or wood heat. Oak Bay, Fairfield, James Bay and Fernwood homes often have two: one for the original kitchen stove and one for the living-room fireplace, and both were flashed with a single strip of galvanized metal and a lot of tar. Sixty years of freeze-free but wet winters have taken the mortar joints and the tar together, so a re-flash on these homes frequently needs a mason first.

Mid-century homes in Gordon Head, Esquimalt and Colwood usually have one wide chimney on the low side of a hip roof, exactly where a cricket, a small peaked diverter behind the chimney, should have been built and rarely was. Water pools behind the chimney, the shingles rot, and the decking with them. Where wood heat has been abandoned, many owners choose to remove the chimney below the roofline during a re-roof and shingle over the hole, which is often cheaper than flashing it properly.

Correct flashing is two layers of metal. Step flashing is a series of L-shaped pieces woven into each shingle course up the sides of the chimney; counter flashing is a second set of pieces let into a saw-cut groove in the mortar joints and bent down over the step flashing so water cannot get behind it. A front apron and a back pan, or a cricket on wide chimneys, complete the set. A repair that consists of new tar over old metal is not flashing; it is a delay, and it explains most of the sub-$400 quotes you will see.

• Step flashing woven with the shingles
• Counter flashing cut into the mortar, not surface-glued
• Cricket behind chimneys wider than about 30 inches
• Ice-and-water membrane under all of it

The cheap end is a narrow chimney on a walkable roof with sound mortar: cut the grooves, form and fit the metal, seal, done in half a day. The expensive end adds any two of: a steep roof needing anchors and ropes, a wide chimney needing a fabricated cricket, mortar too soft to hold counter flashing so a mason must repoint first, or a chimney on a two- or three-storey eave. Our model prices the roofing side at $400 to $1,500 per chimney and treats masonry as a separate trade. RoofingCalculatorHQ's 2026 Canadian range of $310 to $1,250 covers the same spread.

If the roof is otherwise mid-life and the chimney leaks, re-flash now; it is a self-contained job and the leak will rot the decking if left. If the roof is within a few years of replacement, a flashing repair from the $400 to $1,500 repair menu may hold until then, and the full re-flash is done with the new roof so you pay for the metal once. Ask the roofer to state which case you are in and why.

Ask whether counter flashing will be cut into the mortar or surface-mounted, whether a cricket is included or needed, what metal will be used (galvanized, painted steel, copper or lead), and whether the mortar is sound enough to take new flashing or needs a mason first. Ask for photographs of the finished flashing. If the chimney is unused, ask what removing it below the roofline would cost instead; on many 1960s homes it is the better answer.