How to Build a Wood Retaining Wall

How to Build a Wood Retaining Wall

Retaining walls can be a crucial addition to any garden or space. Although they have one function, the result of that function has a wide scope. Retaining walls can be made from more than one kind of material. One of them being wood.

In this blog, we will show you how to build a wood retaining wall.

At PPC Concrete Products, we are here to provide solutions for your construction needs, from the person working their own part-time project, to commercial clients, and everyone in-between.

Monthly construction output had risen an estimated by an 1.6% value in June 2023, and we would like to think our accessible concrete products had a small part to play by giving our clients easy access to reliable and easy-to-use construction solutions.

What is a retaining wall?

Can a fence be used as a retaining wall?

Retaining walls are generally used on land that has slopes, they are used to effectively remove the slope, creating a wall in-between, which can vary in size from a metre, to a few feet!

Without retaining walls, a sloped area of land can be a health hazard in public areas and some gardens. In the case of a garden, a slope can make it an inconvenience to navigate. Essentially, retaining walls work to optimise the land it is set in, which is crucial for areas with heavy foot traffic, or areas that want more useable flat land.

What are retaining walls made from?

Retaining walls have a few materials they can be made from. The usual materials are wood, concrete, bricks, or metal. All have their own pros and cons. If made correctly, all options have the potential to last for a very long time.

How to build a wood retaining wall

How to build a timber sleeper retaining wall

Below, we will share a basic process of building a retaining wall with wood. Please note that the certain information may not apply to you, as the construction of a retaining wall will vary based on the land it is erected on.

Set your boundaries

It is a good idea to set the boundaries of your retaining wall before commencing any construction or digging. Using your plans as a reference, physically mark the opposing ends of your retaining wall, use a stake to create a clear visual indicator of where your retaining wall should end. Tie a string tightly between these posts.

Begin addressing the slope

Using your shovel, begin digging into the slope you are creating the retaining wall for. The amount you dig will depend on the size of the slope, but you are not digging too deep, only sideways. This is to create room for the retaining wall to work. Please note that if you remove a large amount of soil, it will need to be replaced with gravel backfill.

Prep the area

Using the string from before as a reference, follow the line and dig a groove roughly five inches deep. This is where your retaining wall will rest. It must be level, you can use a flat bladed shovel or spade to level areas of the groove, or moving soil.

Mark more areas

Between the two stakes you originally planted, you need to plant more. This will vary depending on the length of your retaining wall, but an equal number that are an equal distance apart is the aim. For now, the stakes are being used to represent the centre position of a post hole.

Dig the holes deeper

Wood retaining walls have a specific rule to ensure they can support the weight it is holding. The height of the soil being held back should roughly be equivalent to the depth of the post holes.

As we highlighted before, retaining walls can vary in size and weight they are holding. Once you have understood the depth you need to dig at for your post holes, add at least another 4 inches (ca. 10 cm) to account for the gravel. Once you’ve done this, remove the stakes and dig into the remaining holes to the relevant depth.

Pouring gravel

Pour 4 inches (ca. 10 cm) of gravel into each post hole that you have just dug. Avoid allowing soil into them.

Prepare your posts

Ensure the parts of your post that will be going in the post holes have wood preservative over them. After this, place it into the hole, ensuring the post is perfectly aligned and straight. You can use the stakes you had before as a way of holding the posts in place.

Pouring concrete into the post hole

Ideally, you should use a quick setting concrete, begin by pouring the powder in the hole, followed by the instructed mount of water. Let the concrete fully dry before moving onto the next hole. This drying time will vary depending on the concrete you use.

Adding gravel to the groove

Remember that groove you dug earlier? Well, once all your posts have had their concrete poured and set, add around two inches of gravel to the groove. This helps drainage and reduces the effects of water to your retaining wall.

Board it up

Your retaining wall is slowly coming together. Add the wooden boards that will make the wall itself. Make sure you add these boards from the slope side of the wall.  Starting from the top of your wall and working your way down. Ensure that your top boards are flush with the top of the posts. When you’ve made it to the bottom, your final boards should be around 2 inches (ca. 5 cm) below ground level.

Add more gravel and soil

On the slope side of your retaining wall, distribute the rest of your gravel evenly. This is key in promoting proper drainage for your retaining wall. If you neglect doing this, the resulting weight on your retaining wall, especially in wet conditions, will be too much for your wall to sustain. After this, backfill the rest of the cavity with soil.

Is there an easier way to make a retaining wall?

Create a retaining wall today

The easiest, and fastest way to create a retaining wall is through the use of Interlocking Concrete Blocks. Interlocking Concrete Blocks do not require the need for digging posts, their heavyweight nature, and additional interlocking capability makes them the superior option for holding the weight of a retaining wall.

Furthermore, they are available in multiple sizes, making them applicable to large retaining walls, or a small garden based retaining wall.

Unlike bricks, Interlocking Concrete Blocks require no binding materials whatsoever. This saves time that would otherwise be spent on cement drying. Once your Interlocking Concrete Blocks are interlocked, they can not be undone without physical intervention.

How much are Interlocking Concrete Blocks?

The cost of Interlocking Concrete Blocks are dependent on the amount required, in addition to the size. For an accurate quote, we would recommend contacting us directly and discussing your project. We suggest having your plans on hand for the most accurate quote.

Enquire about retaining walls today

As an established supplier all over the UK, PPC Concrete Products is always happy to help, which is why we encourage you to get in touch with any questions you may have or have a look at our FAQ.

In this blog, we hope to have clearly displayed how to build a wood retaining wall, whilst also providing additional information including construction solutions that we offer.

Take a read of our case studies to truly understand how we have provided solutions for business in the past with the use of our interlocking concrete blocks, and ultimately, how we can help you today.

Read our blog page for more insights into our passion, construction.


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