How much does a retaining wall cost

Factors in a Retaining Wall Cost Quotation

One of the main factors in the cost of your retaining wall is which material you choose. Stonework is the most expensive option but also one of the most aesthetic and may be desirable to reflect a period property’s style.

Timber sleeper retaining walls are the lowest cost option – although you will need to ensure your timbers are appropriately treated to make sure rot and damp don’t set in.

The below list shows some of the most popular retaining wall materials and what sort of pricing you’re looking at per metre from highest to lowest:

• Stonework retaining walls – from £325 per metre.
• Concrete retaining walls – from £220 per metre.
• Gabion retaining walls – from £200 per metre.
• Brickwork retaining walls – from £195 per metre.
• Blockwork retaining walls – from £180 per metre.
• Timber sleeper retaining walls – from £105 per metre.

Materials aren’t the only cost factor, and you’ll also need to think about the height of the wall and the amount of labour required. UK average labour costs come to £160 per person per day.

Complex structures and intricate retaining walls may require specialist tradespeople, who tend to charge a higher daily or hourly rate.

Your retaining wall may also need foundations, typically made from poured concrete. The volume required and any clearance work needed before the wall build can start will impact the overall quotation.

Additional Budget Considerations in Building a Retaining Wall

As well as the wall itself, you’ll need to consider the associated costs in planning for your retaining wall construction.

Elements include:

• Structural engineer visits or assessments, necessary for taller walls and costing around £270 per visit.
• Delivery costs to get the raw materials to the site. These are usually higher in London and the southeast and in more rural areas where travel distances are longer.
• Land clearance to ensure contractors can lay the foundations and that there is sufficient space to work. Averages cost around £1,200 per acre of land cleared.

The longer and taller your retaining wall, the higher the costs. Simple, small retaining walls can cost as little as £45 per hour in labour, plus materials.

Larger retaining walls in crucial positions may need advice from an engineer, with an average 8-foot high wall costing around £10,500.

If you are building a retaining wall close to your house, you must make sure this will not impact any drainage systems. If you find your construction plans will affect a drainage area, you can request a Drain Survey Quote or a Drainage Repair Quote via our online service. You will also need to make sure that the area is secure or appropriate for outbuildings or other garden structures. Take a look at our page on brick shed costs for more information on these structures.

Likewise, it’s crucial to inspect the land underneath the new retaining wall to make sure there aren’t any gas mains – you can also request a Gas Engineer Callout if you have any concerns.

Breaking Down a Retaining Wall Cost Quote

Quotes will usually be itemised to help you understand where each part of the cost comes from. Still, if anything isn’t clear, it’s best to raise this with your contractor before work begins.

A typical quote will look like this:

• Wall unit materials – bricks, stone blockwork etc., priced per metre.
• Logistics charges – delivery fees for the materials to be transported to the site.
• Clearance cots – charges based on skip hire and labour hours to ready the area.
• Preparation costs – time and materials required to lay a concrete foundation.
• Installation – labour time and any other association materials required to fix the wall materials in place.

Given that retaining walls can be an essential way to stabilise land, shore up ditches and prevent land slippage, it’s worth looking for at least three quotes to ensure you’re paying a fair price.

However, it’s also vital to use a suitably qualified professional to ensure the work is completed to a higher standard and is strong enough to last for years.

What are the Main Uses of a Retaining Wall?

If you’re considering a retaining wall cost, it remains vital to assess what you need this for and whether there are any alternatives.

The primary reasons for erecting a retaining wall include:

• Stabilising land on a steep slope to avoid slippages.
• Preventing accidents from mudslides.
• Avoiding soil erosion.
• Building raised flower beds or landscaping areas.

One of the most significant cost factors will always be the materials used, so if you’re on a budget, you could consider building timber sleeper retaining walls, which will be faster and cheaper to erect than a stonework construction.

FAQs - Building a Retaining Wall

Let’s answer some of the most commonly asked questions about building a retaining wall in your garden!

What is a Retaining Wall Used For?

Retaining walls are typically used in outdoor spaces to retain earth and soil. That might be for aesthetic reasons to level out a lawn, for example, or to protect against risks such as slippage and mudslides.

This wall may need to have a solid concrete base (or be stabilised on compacted earth) to ensure it has good drainage and won’t erode over time.

Which Type of Retaining Wall Do I Need?

A lot depends on the soil in your garden and your reasons for erecting a retaining wall. For example, sand or clay soil might require a different foundation, and your wall needs to be tall and robust enough to support the necessary volume of earth.

How Much Does it Cost to Replace a Retaining Wall?

If you already have stable foundations and need to repair or replace one portion of your wall, the costs will be much lower than for a new build.

The average cost for a retaining wall repair is around £4,000 depending on what materials it is built from and how much work is required to replace the damaged section.

What are the Most Popular Construction Methods for a Retaining Wall?

There are four primary types of retaining wall:

• Gravity retaining walls rely on the wall’s weight to hold back the soil and withstand the pressure.
• Gravity inclined walls use fewer blocks and are designed to use gravity along with an inclined construction.
• Cantilever walls are built in an L-shape and use reinforced concrete. This type of wall required very deep excavations.
• Criblock walls use concrete or timber frames filled with stone.

Do I Need Planning Permission to Build a Retaining Wall?

Possibly, yes. If the wall is over a metre high and next to the road, or over two metres high elsewhere, you may need planning permission.

Freestanding retaining walls don’t typically need building regulation approval, but more significant integrated constructions might.

It’s always best to check with your local planning authority if you have any concerns about permission for your work.