200x75mm & 200x100mm Concrete Sleepers

Concrete Sleepers by Size — 200x75mm & 200x100mm

Choosing the right sleeper thickness is one of the most important decisions in any retaining wall project. Our 200x75mm and 200x100mm concrete sleepers are the two most widely used sizes across residential, landscaping, and light commercial retaining walls in Australia — strong, durable, low-maintenance, and compatible with standard galvanised steel posts.

Which Size Do You Need?

200x75mm Concrete Sleepers

The 200x75mm sleeper is the standard choice for low to medium height retaining walls — typically up to around 900mm to 1.2m finished height depending on post spacing, soil conditions, and surcharge loads. It's the most common size for garden beds, level changes, driveway edges, and landscaping walls where loads are light and the wall is freestanding.

200x100mm Concrete Sleepers

The 200x100mm sleeper offers greater bending strength and is the preferred choice for walls over 1.0m, walls retaining heavy or wet soils, walls near driveways or structures, and any situation where additional load capacity is required. The extra 25mm of thickness makes a significant difference to structural performance at height.

Important: For walls over 1.0m in height, near boundaries, structures, or with surcharge loads (driveways, vehicles, buildings), always confirm specifications with a licensed structural engineer or building certifier. Council approval may also be required depending on your state and wall height.

Available Finishes

Both sizes are available in three finishes to suit your project aesthetic:

• Charcoal concrete sleepers — a clean, contemporary dark finish that suits modern landscaping and complements steel posts and gravel.
• Woodgrain concrete sleepers — the natural look of timber with the strength and longevity of concrete. No rot, no termites, no repainting.
• Smooth finish concrete sleepers — a flat, paintable surface ideal for rendered or painted wall finishes.

Compatible Steel Posts

All 200x75mm and 200x100mm sleepers are designed to slot into standard galvanised steel retaining wall posts. Choose from H-beam steel posts for maximum strength on taller or heavier walls, or C-channel PFC posts for cost-effective performance on lighter walls. Post spacing is typically 1.8m to 2.4m depending on wall height and soil conditions.

Don't Forget Drainage & Hardware

A concrete sleeper wall without proper drainage is a wall that won't last. We stock a full range of drainage kits for retaining walls including ag pipe, geotextile fabric, and weep holes, plus all the retaining wall hardware and brackets you need to finish the job properly.

If you're starting from scratch, check out our retaining wall starter kits — sleepers, posts, and drainage bundled together for easy ordering.

Why Choose Retaining Walls Direct?

• Trade and retail pricing with no minimum order on standard sizes
• Australia-wide delivery to metro and regional areas
• Expert advice from people who actually know retaining walls
• Full range of compatible posts, drainage, hardware, and accessories

Not sure which size or finish is right for your project? Contact our team — we're happy to help you spec it correctly before you order.