When it comes to retaining walls in Melbourne, two systems come up again and again: concrete sleepers with steel posts, and concrete block (Besser block) walls. Both are durable, both are widely used — but they suit different situations, budgets and skill levels.

Here's a straight comparison to help you decide which is right for your project.

What Are Concrete Sleeper Retaining Walls?

Concrete sleeper walls use precast reinforced concrete panels (sleepers) that slot horizontally between vertical steel H-posts or C-posts. The posts are set in concrete footings, and the sleepers stack between them to form the wall face.

At FPM, our concrete sleepers are manufactured from 50 MPa reinforced concrete and are available in five finishes: plain grey, charcoal, woodgrain, blockface (rockface), and stackstone. Standard lengths are 1985mm and 2985mm; thicknesses are 75mm and 100mm.

What Are Concrete Block Retaining Walls?

Concrete block walls — commonly called Besser block walls — use hollow or solid masonry units stacked in courses and bonded with mortar. Reinforcing steel (reo bar) is typically run vertically through the hollow cores, which are then filled with concrete grout to create a reinforced masonry wall.

At FPM we stock standard hollow concrete blocks (390×190×190mm), solid concrete blocks, and besser blocks suitable for retaining wall construction.

Side-by-Side Comparison

Factor	Concrete Sleepers + Posts	Concrete Block Wall
Typical wall height	Up to 3.0m (engineered)	Up to 2.4m (standard)
Upfront material cost	Moderate	Moderate–High
Labour / installation	Moderate — post setting + sleeper stacking	Higher — mortar, reo, grout, curing
DIY-friendly	Yes, with machinery for posts	Challenging — requires masonry skills
Aesthetics	Range of finishes; modern or textured	Industrial; can be rendered or painted
Engineering requirement	Required above 1.0m (VIC)	Required above 1.0m (VIC)
Drainage	Weep holes between sleepers	Weep holes must be built in
Maintenance	Very low	Very low (if rendered, may need repainting)
Lifespan	50+ years	50+ years
Repair	Individual sleepers replaceable	Difficult to repair sections

Strength and Engineering

Both systems can be engineered to handle significant lateral soil loads. The key difference is in how they resist that load:

Concrete sleeper walls transfer load through the sleepers into the steel posts, which act as vertical cantilevers anchored in concrete footings. The post size, embedment depth, and sleeper thickness are all specified by the engineering calculations — which is why FPM provides engineering certificates for our sleeper systems.

Concrete block walls resist load through the mass and reinforced core of the wall itself. A properly reinforced and grouted block wall is extremely strong, but it requires careful construction — the reo must be correctly placed and the cores fully grouted for the wall to perform as designed.

For walls over 1.0m in Victoria, both systems require engineering sign-off. Check our Engineering page for wall height specifications and downloadable engineering certificates for FPM sleeper systems.

Installation: Which Is Easier?

Concrete Sleeper Walls

Installing a concrete sleeper wall involves:

1. Setting out post positions (typically 1985mm or 2985mm centres)
2. Drilling or excavating post holes to the required depth
3. Setting posts in concrete and allowing to cure
4. Stacking sleepers between posts from the bottom up
5. Installing drainage (ag pipe, geofabric, drainage aggregate) behind the wall

The post-setting step typically requires a post-hole digger or excavator for anything beyond a low garden wall. Once posts are set, stacking sleepers is straightforward — though at 80–100kg per sleeper, you'll need at least two people and ideally a machine for taller walls.

Concrete Block Walls

Block wall construction involves:

1. Excavating and pouring a concrete strip footing
2. Laying blocks in courses with mortar, maintaining level and plumb
3. Installing vertical reo bar at specified centres
4. Filling hollow cores with concrete grout
5. Allowing adequate curing time between stages
6. Building in weep holes for drainage
7. Backfilling and compacting in stages

Block work requires masonry skills and patience. Getting courses level and plumb, achieving consistent mortar joints, and correctly placing and grouting reo all take experience. It's not impossible for a capable DIYer, but mistakes are hard to fix once mortar sets.

Verdict: For most DIY and trade retaining wall projects, concrete sleepers are faster and more forgiving to install. Block walls suit projects where a rendered or painted finish is desired, or where the wall needs to integrate with existing masonry construction.

Cost Comparison

Cost varies significantly with wall height, length, and site conditions, but as a rough guide for a standard 1.2m high × 10m long wall in Melbourne:

Concrete sleeper wall:

• Posts (6 × H-posts at appropriate length): $600–$900
• Sleepers (approx. 30 × 75mm sleepers): $900–$1,200
• Concrete for post footings: $150–$250
• Drainage materials (ag pipe, geofabric, aggregate): $300–$500
• Materials total: approx. $1,950–$2,850

Concrete block wall:

• Strip footing concrete: $400–$600
• Blocks (approx. 130 blocks): $650–$900
• Mortar, reo, grout: $300–$500
• Drainage materials: $300–$500
• Materials total: approx. $1,650–$2,500

Block walls can be slightly cheaper on materials for lower walls, but the additional labour time (especially if hiring a bricklayer) often makes the total installed cost higher than a sleeper wall.

Aesthetics

This is where the two systems diverge most clearly.

Concrete sleeper walls offer a range of contemporary finishes straight out of the box. Woodgrain and stackstone finishes in particular look excellent in modern landscaping without any additional treatment. The horizontal banding of the sleepers creates a clean, structured look.

Concrete block walls in their natural state have an industrial, utilitarian appearance. They're often rendered and painted to improve aesthetics — which adds cost and ongoing maintenance (paint eventually needs refreshing). Left unrendered, they suit industrial or commercial settings better than residential gardens.

If aesthetics matter and you don't want to render, concrete sleepers are the better choice for most residential projects.

When to Choose Concrete Blocks

Concrete blocks make sense when:

• You're building a wall that will be rendered and painted to match existing masonry
• The wall needs to integrate with a house foundation or existing block construction
• You want a very thick, massive wall (e.g. for a raised planter or feature wall)
• A bricklayer is already on site for other work
• The wall is in a location where post-hole drilling is difficult (e.g. near existing footings)

When to Choose Concrete Sleepers

Concrete sleepers are the better choice when:

• You want a finished look without rendering or painting
• The wall is over 600mm high and needs engineering
• You're doing the work yourself or with a landscaper (not a bricklayer)
• Speed of installation matters
• You want individual panels to be replaceable if damaged
• The wall is in a residential garden setting

Drainage: Don't Skip It

Regardless of which system you choose, drainage behind the wall is critical. Hydrostatic pressure from waterlogged soil is the number one cause of retaining wall failure.

For both systems, you should install:

• Geofabric against the back of the wall to prevent soil migration
• Drainage aggregate (20mm crushed rock) behind the wall
• Ag pipe (slotted agricultural drainage pipe) at the base of the wall, running to a legal discharge point

See our retaining wall drainage guide for full details.

What Does FPM Stock?

At FPM Building Supplies in Epping, we stock everything you need for both systems:

For concrete sleeper walls:

• Concrete sleepers in 75mm and 100mm thickness, five finishes
• Galvanised steel H-posts and C-posts in multiple lengths
• 150×150 UC posts for engineered applications
• Geofabric, ag pipe, and drainage aggregate
• Engineering certificates for our sleeper systems

For concrete block walls:

• Standard hollow concrete blocks (390×190×190mm)
• Solid concrete blocks
• Besser blocks
• General purpose cement and rapid-set concrete

Come in and see us at 32 Fullarton Drive, Epping VIC 3076, or call us on +61 431 235 919. We're happy to help you work out quantities and choose the right system for your project.