Chilliwack: current official fence source
The current official Chilliwack fence/zoning/planning source is linked below, but the evidence does not support one safe city-wide numeric fence-height answer without more property context. Open the source for the applicable lot, zoning, corner and other conditions.
Open Chilliwack official fence/zoning source ↗Nearby communities in Fraser Valley may use different yard definitions or heights, so the Chilliwack rule should be checked on its own terms.
The four fence checks that change the answer
Front, side or rear?
Do not carry a rear-yard maximum into the front yard. Municipal tables commonly separate those locations.
Corner or driveway?
Near a driveway or intersection, the municipality may care more about clear sightlines than the usual fence limit.
Pool or hot tub?
Water-safety enclosures can add minimum heights and gate controls, so a standard fence design may need changes.
Retaining wall?
A fence on a retaining wall may need a different approval route than the same panel installed at natural grade.
One more Chilliwack site check
Walk the proposed line from end to end and note where it crosses yard categories, changes grade or approaches a driveway, corner or pool.
A survey can prevent a zoning-compliant fence from becoming a boundary dispute. Treat those as two separate checks.