Timber sleeper retaining walls.
The most economical option for residential retaining. Done right, a treated pine wall lasts 15–25 years; a hardwood wall lasts 30–40+ years. Done wrong, either fails in five.
Three timber wall systems — pick by lifespan and budget.
1. H4 treated pine sleepers
The most common choice. CCA-treated pine sleepers, 200×75mm or 200×100mm, slid between hot-dipped galvanised C-section posts cored into concrete.
- Cost: $250–$320/m² installed
- Lifespan: 15–25 years
- Best for: walls under 1.2m, garden beds, fence-line walls, budget-driven jobs
2. H5 in-ground treated pine
Heavier preservative treatment for in-ground contact. Worth the extra cost on damp sites or where you want closer to a 25–30 year lifespan.
- Cost: $290–$360/m² installed
- Lifespan: 25–30 years
- Best for: wet ground, walls on the south side of the house, longer-life budget jobs
3. Australian hardwood (red gum, ironbark, jarrah)
Genuine hardwood sleepers. Heavy, dense, naturally rot-resistant. Looks beautiful and lasts a generation.
- Cost: $360–$450/m² installed
- Lifespan: 30–40+ years
- Best for: feature walls in the front yard, premium homes, "build it once" jobs
What we won’t do
We don’t use H3-rated pine for retaining (only above ground), we don’t skip the drainage zone to save $80, and we don’t use star pickets or treated pine posts. Galvanised steel posts only. There’s a reason cheap walls fail.
Free timber wall quote.
Site visit, fixed price, written quote within 48 hours.