Building a small retaining garden wall from new sleepers
The GardenAdvice MyGardenTeam helps you get your gardening projects right first time
One of the quickest and most cost-effective ways of creating a low garden wall is by using new softwood railway sleepers set into the ground. When designed and installed correctly, sleeper walls are strong, adaptable, and visually well suited to both modern and informal garden layouts.
At GardenAdvice, we regularly help clients use sleeper walls to define garden levels, edge driveways, retain banks, and create raised planting areas — all while ensuring the structure is safe, durable, and appropriate for the site.
Why Choose Railway Sleepers for a Garden Wall?
New treated softwood railway sleepers offer several advantages:
- Consistent size and appearance
- Easier to handle and cut than reclaimed sleepers
- Pressure treated for durability and resistance to rot
- Free from contaminants often found in old railway sleepers
Sleepers can be installed in straight lines or gentle curves, making them highly flexible for garden design. Once installed, they can be left at random heights for a natural look, or cut to a straight or sloping finish using a chainsaw for a more formal appearance.
A Typical GardenAdvice Project Example
In this example, sleepers have been installed at the edge of a driveway, positioned at the bottom of a bank. Because of the change in ground levels, the wall will act as a small retaining wall, not just a decorative feature.
This is a key point that is often overlooked in DIY garden projects:
once a wall is holding back soil, even at low height, it must be designed as a retaining structure.
Retaining Walls: Structure Is Crucial
For retaining situations, GardenAdvice would never recommend relying on sleepers alone. Instead, the correct approach is to:
- Construct a reinforced concrete retaining wall behind the sleepers
- Use the sleepers as the visible facing
- Ensure the wall is properly founded and reinforced
This provides the necessary strength while retaining the natural timber appearance that clients want.
Through GardenAdvice MyGardenTeam, we help clients understand when additional structure is required and ensure the right construction methods are used from the outset.
Drainage: The Most Common Cause of Failure
Most retaining wall problems — regardless of size — are not caused by the weight of the soil, but by the build-up of water behind the wall.
Waterlogged soil becomes extremely heavy and creates significant pressure. Without drainage, walls can bow, lean, or fail completely.
Essential Drainage Measures
In this type of installation, GardenAdvice would specify:
- A perforated land drain behind the wall
- Free-draining aggregate around the drain
- A suitable outlet or soakaway to remove water from the system
Installing drainage is critical, not optional. Removing water from behind the wall dramatically reduces pressure and extends the life of the structure.
How GardenAdvice MyGardenTeam Helps
The GardenAdvice MyGardenTeam service is designed to help clients and viewers confidently plan and carry out garden projects, whether they are managing the work themselves or coordinating contractors.
With MyGardenTeam, you can receive:
- Clear guidance on whether a wall is decorative or structural
- Advice on foundations, drainage, and construction methods
- Help choosing appropriate materials for longevity and safety
- Ongoing support during the build if questions arise
This ensures projects such as sleeper retaining walls are not only attractive but also technically sound.
Installation, Finishing, and Longevity
Key considerations we help clients with include:
- Correct setting depth and foundations
- Fixing methods between sleepers
- Allowing for drainage and ground movement
- Protecting cut ends of timber
Softwood sleepers will weather naturally over time, but with good drainage and sound construction, they can perform very well in low retaining roles for many years
Low railway sleeper walls are a versatile and economical solution for many garden situations. However, when they retain soil, careful attention to structure and drainage is essential.
GardenAdvice MyGardenTeam helps bridge the gap between inspiration and correct construction, giving clients the confidence to create gardens that look good and last.
If you’d like guidance on a sleeper wall or any other garden project, the MyGardenTeam service is here to help every step of the way.