There is no single Canadian fence-height limit
Residential fence height is usually regulated locally, so the usable number depends on the municipality and the part of the lot. Front yards, rear yards, interior side yards and a side yard beside a street can all be treated differently. A fence that is ordinary in one city can require approval in another.
Start by identifying the yard correctly
Do not assume the side facing your driveway is automatically the front yard. Corner lots, through lots and irregular parcels can change which lot line is treated as front, rear or flanking. That matters because lower limits are commonly used where a tall fence could affect visibility from a street or driveway.
Current city rules show why local checking matters
For example, Calgary's current fence guidance says a permit is typically required when a fence exceeds 1.2 m in a front yard, 2.0 m in a rear yard, or 0.75 m inside a corner visibility triangle. Edmonton's current guidance uses 1.3 m for front yards and 2.0 m for rear or interior side yards before an over-height development permit is required. Those are two large Alberta cities with different thresholds and different site conditions.
See the City of Calgary fence and retaining-wall guidance and the City of Edmonton fence permit guidance.
Height is not the only rule
Even when the proposed height is within the ordinary limit, separate rules may apply to corner visibility, pools and hot tubs, retaining walls, gates, materials, easements or restrictive covenants. A fence can therefore be permit-free and still be non-compliant.
Use the number only after checking the property
Before ordering materials, confirm the municipality, zoning context, yard location, grade and any special feature beside the fence. If the property is close to a municipal boundary, use the authority responsible for the actual parcel rather than the nearest city name.