Ontario Fence Laws: Height, Ownership and Neighbour Rules

Before you put up or replace a fence, you probably want to know how high it can be, whether you need a permit, and whose it will be once it is built. People often expect one provincial rulebook. In Ontario, the answer is split between provincial laws and your own municipality.

This article walks through the main layers: local by-laws, the Line Fences Act, trees on the boundary, and what to do when you are unsure where the boundary is.

Height and design come from your municipality

Municipalities may pass by-laws about structures, including fences. That means fence height and design rules come from local by-laws, not a single provincial rule. A fence that is acceptable in one city may not be in the next town.

Details such as maximum height, materials, pool enclosures and setbacks can all differ by location, so check your municipality's fence by-law and ask whether a permit is needed before you buy materials. If a by-law sets height or construction, a fence described in a fence-viewers' award must comply with it.

Building on the boundary and who owns the fence

An owner of land may build, maintain and keep up a fence that marks the boundary between their land and their neighbour's land. Where a line fence is disputed, the Line Fences Act process can divide the work and describe the fence, but it does not decide where the property line is.

Sometimes the land makes it impractical to build exactly on the line. An award may then place the fence partly on either owner's land, and that location does not affect who owns the land. In a registered condominium, the condominium corporation, not the individual unit owner, is treated as the owner for Line Fences Act purposes.

How the cost and care of a shared fence are handled between you and your neighbour depends on your situation, so it is worth confirming with a lawyer. Neighbours may make a written agreement about a line fence on the prescribed form (Forms 14 and 15), and that agreement may be registered and enforced as if it were a fence-viewers' award. Putting any agreement in writing avoids later arguments.

When neighbours disagree about a fence

The Line Fences Act arbitration process applies when owners cannot agree and either there is no fence and one owner wants one, or there is a line fence that one owner thinks should be repaired or rebuilt. It does not apply if one owner has already built or repaired a fence on their own and then asks the neighbour to share the cost. Municipalities may also opt out of the Act for all or part of their area, so confirm it applies where you live.

• Fence-viewers may decide how the work is divided and the description of the fence, including materials.
• They must consider how suitable the fence is for each owner's needs.
• An owner who wants to remove a line fence must generally give the neighbour at least six months' notice.
• If a tree falls on a line fence, the owner or occupant of the land where the tree stood must immediately remove it and repair the fence.

Trees on the boundary

A tree whose trunk grows on the boundary between neighbouring lands is the common property of the owners of both lands. Anyone who injures or destroys such a tree without the landowners' consent commits an offence under the Forestry Act. On conviction, the penalty can be a fine of up to $20,000, up to three months in prison, or both. An owner may plant trees on the boundary only with the neighbouring owner's consent.

Rules about overhanging branches, roots, or municipal tree-protection by-laws vary and are worth confirming locally before you cut anything.

What to do next

If you are unsure where the boundary lies, a survey is the usual starting point. Only licensed individuals, or people working under a licensed member's direction and supervision, may practise cadastral surveying, which includes preparing plans that determine a boundary. Where there is doubt about a boundary's true location, an application can be made to the Director of Titles under the Boundaries Act, and a confirmed and certified boundary is deemed the true boundary.

• Read your municipality's fence by-law and ask whether a permit is required.
• Talk to your neighbour before building and agree on cost and design in writing.
• Get a survey if the boundary is uncertain.
• Do not cut or damage a tree on the boundary without both owners' consent.
• See a lawyer if the dispute involves title, possession or a long-standing boundary.

Frequently asked questions