Thornhill plumbers for older pipes, drains and backwater valves

Older homes and rebuilds on both sides of Yonge — tell us what's going on and a local plumber who covers Thornhill gets back to you with a quote.

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Thornhill straddles Yonge Street: the west side is in the City of Vaughan, the east side in the City of Markham. It has one of the older housing stocks we cover — the old village around Yonge Street and Centre Street, streets of 1950s and 1960s homes, large 1970s and 1980s subdivisions — and a steady stream of teardowns and rebuilds.

In the older houses, the problems are the ones age brings: galvanized or early copper supply lines, cast-iron drain stacks, and clay or cast-iron sewer laterals under mature trees that block again and again. A camera inspection is usually the first step with a main drain that keeps backing up.

Which side of Yonge you are on decides which city handles permits and any basement flooding program. Tell us your street or nearest intersection and what is going on, and your request goes to one plumber who covers Thornhill.

York Simcoe Plumbing is a free referral service: your request goes to one independent local plumber serving Thornhill, and they quote and do the work.

Common Jobs in Thornhill

Main drains and tree roots on older Thornhill streets

Older laterals under big trees are the classic Thornhill backup. Clearing restores flow; a camera shows whether the roots will be back.

Drain clearing and sewer lines →

Backwater valves for older basements

Many Thornhill homes were built before backwater valves were common. Ask Vaughan or Markham, depending on your side of Yonge, whether a subsidy program is running.

Sump pumps and backwater valves →

Galvanized and older supply lines

Low pressure, rusty water or pinhole leaks in older supply pipe often mean it is time to replace a section, or the whole run.

Emergency leaks and burst pipes →

Tell us about your job in Thornhill

Thornhill Questions, Answered

It depends which side of Yonge Street you are on. West of Yonge, Thornhill is in the City of Vaughan; east of Yonge, it is in the City of Markham. Permits and any municipal programs go through that city.

Galvanized steel supply pipe corrodes from the inside, which shows up as low pressure, rusty water and, eventually, leaks. Many owners replace it when they renovate or when problems start. A plumber can look at what you have and tell you how much of it is left.

Many homes built before the 1970s used cast-iron drain stacks, and some have cast-iron or clay sewer laterals. Cast iron lasts a long time but eventually cracks or corrodes, often along the bottom of horizontal runs. A camera inspection is the usual way to see its condition without opening walls.

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Plumbers Near Thornhill

Concord Vaughan Richmond Hill Markham North York Unionville All service areas

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York Simcoe Plumbing is a free referral service: your request goes to one independent local plumber, who quotes and does the work. We may receive compensation when you are connected with a plumber; there is no charge to you.