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Chimney Flashing Repair in O'Neill, Oshawa

Professional chimney flashing repair in O'Neill, Oshawa — 24 hour response, licensed & insured.

Call (437) 475-2233
24 hour response
Licensed & insured
OEM parts on the truck

Where your chimney meets the roof in O'Neill, Oshawa is the single most leak-prone spot on your entire home. Proper chimney flashing has two layers — step flashing woven into the shingles and counter-flashing tucked into the brick mortar joints. When either fails, water tracks straight into the wall.

Why chimney flashing repair matters in O'Neill, Oshawa

Two-Layer System

Real chimney flashing is a two-part system. Anyone offering to 'just caulk it' is selling you a 12-month fix.

Mortar Cut Matters

Counter-flashing must be cut into the mortar joints — not surface-mounted. Surface-mount flashing on a chimney lasts one winter.

Ice And Water Shield

A proper chimney rework includes ice-and-water membrane under the flashing for a redundant seal.

Our chimney flashing repair process

  1. 1

    On-Site Assessment

    We walk the exterior in O'Neill, Oshawa, document current condition with photos, and identify every failure point before quoting.

  2. 2

    Written Quote

    You get an itemized estimate — parts, labour, timeline — before any work starts. No surprises.

  3. 3

    Professional Repair

    Our crews use manufacturer-approved materials and industry-standard techniques. Every job is fully insured.

  4. 4

    Cleanup & Verify

    We haul away debris, sweep the work area, and walk the finished job with you before signing off.

  5. 5

    Warranty

    Every job in O'Neill, Oshawa carries a written labour warranty and full manufacturer coverage on materials.

Common findings in O'Neill, Oshawa

  • Surface-mounted counter-flashing pulling away from brick
  • Rusted galvanized flashing from years of moisture
  • Missing kick-out flashing at the roof-wall junction
  • Caulk-only 'repairs' from prior contractors

What you get

Real Craftsmanship

Experienced tradespeople in O'Neill, Oshawa — not day labour — on every job.

Fair, Upfront Pricing

Written quotes before we start. No day-of surprises.

Peace Of Mind

Licensed, insured, and warrantied. If something isn't right, we come back.

Chimney Flashing Repair reviews in O'Neill, Oshawa

4.9 average from 743 verified customer reviews
Clean, quiet, respectful
Shoe covers, sheeting, and a sealed vacuum. My wife works from home and barely noticed they were here.
Peter N. - Oshawa - 2026-01-15
Honest about what I did not need
They told me the flue did not need sweeping yet and charged only for the inspection. First contractor in years to talk me out of spending money.
Nadia F. - Richmond Hill - 2026-06-19
Second flue done same visit
Old house with a furnace flue as well. They handled both in one visit and discounted the second one rather than charging full price twice.
Hannah J. - Pickering - 2026-03-29
Camera scan caught a cracked tile
Previous company swept and said everything was fine. Diamond ran a camera and showed me a cracked liner tile on screen. Glad I got the second opinion.
Marta S. - Mississauga - 2025-11-30

FAQ

Why did my flashing fail?

Almost always because it was surface-mounted and caulked instead of cut into the mortar.

Do you cut into the brick?

Yes — that's the only way to do this repair properly. It's called a reglet cut.

Timeline?

Most chimney re-flashing jobs are a same-day, one-crew job.

Book your chimney flashing repair today

24 HOUR RESPONSE GUARANTEED — call now to lock in a slot in O'Neill, Oshawa.

Call (437) 475-2233

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