Poor drainage is the #1 cause of retaining wall failure. Every wall needs proper drainage to prevent hydrostatic pressure buildup.
Essential Components
- Ag pipe: Perforated pipe at the wall base
- Gravel backfill: 300–500mm drainage layer behind the wall
- Weep holes: Every 1–2m for solid-face walls
Perth Specifics
Perth’s sandy soils drain well generally, but clay pockets in foothills suburbs (Armadale, Gosnells) need extra attention. Occasional heavy rain events demand reliable drainage capacity.
Browse wall types for material-specific drainage requirements. Get quotes from builders who prioritise proper drainage.
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