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Roof Flashing Repair in Thornhill, Markham

Professional roof flashing repair in Thornhill, Markham — 24 hour response, licensed & insured.

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

Roof flashing seals the joint between shingles and any wall, chimney, skylight, or vent that penetrates the roof in Thornhill, Markham. It's also the number-one source of roof leaks — over 70% of leak calls trace back to failed flashing, not shingles.

Why roof flashing repair matters in Thornhill, Markham

The #1 Leak Source

When a homeowner says 'my roof leaks', 7 times out of 10 the shingles are fine and the flashing has failed.

Step Flashing Matters

Continuous flashing bent along a wall fails in years. Step flashing woven between courses of shingles lasts decades.

Skylight & Vent Boots

Rubber vent boots crack in Canadian sun. Replacing them is a 30-minute job that prevents drywall damage.

Our roof flashing repair process

  1. 1

    On-Site Assessment

    We walk the exterior in Thornhill, Markham, 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 Thornhill, Markham carries a written labour warranty and full manufacturer coverage on materials.

Common findings in Thornhill, Markham

  • Failed caulk on continuous chimney flashing
  • Missing step flashing on old wall junctions
  • Cracked plumbing vent boots
  • Corroded skylight flashing kits

What you get

Real Craftsmanship

Experienced tradespeople in Thornhill, Markham — 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.

Roof Flashing Repair reviews in Thornhill, Markham

4.9 average from 743 verified customer reviews
Bundled two services, saved the trip fee
Had the chimney and the dryer vent done on the same visit. Cheaper and half the disruption.
Farah N. - Markham - 2025-12-27
Reliable across three jobs
Used them for a sweep, a dryer vent, and a fireplace service. Same standard every time and the same technician twice, which I appreciated.
Helena B. - Toronto - 2026-04-17
A real person answers the phone
No call centre, no chasing. Booked in two minutes and got a text when the truck was on the way.
Ryan K. - Mississauga - 2026-02-28
Documentation on everything
Photos, readings, and a written summary after every visit. Makes it easy to keep records for the house file.
Doug T. - Burlington - 2026-01-11

FAQ

Can flashing be repaired or must it be replaced?

Small caulk failures are repair; failed step or counter-flashing needs full re-flashing.

What materials?

Aluminum, copper, or galvanized steel depending on the location and existing metal.

Warranty?

10-year workmanship warranty.

Book your roof flashing repair today

24 HOUR RESPONSE GUARANTEED — call now to lock in a slot in Thornhill, Markham.

Call (437) 475-2233

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