Tips for choosing timber for retaining walls

Retaining walls are a crucial part of landscaping. From separating spaces in a garden to holding back loose soil from a public path, they bring both aesthetic and functional benefits to outdoor spaces. But which timber should you choose to build yours? From budget constraints to damp issues, our EcoChoice timber experts have put together everything you need to know to make the right choice.

Durability Class 1 Timbers

A lot of people make the mistake of choosing simply between hardwoods and softwoods when building a retaining wall. The reason we would advise against this is that not all softwoods are less durable or strong than hardwoods, and not all hardwoods have the durability you need. Instead, we would advise looking at their durability classes, which categorise timber species depending on their resistance to external threats.

If your retaining wall is in use class 4 – direct contact with the ground (as itis likely to be), you will be best suited to a durability class 1 timber. These are some of the ground projects where timber comes in direct ground contact, and can deal with constant dampness and the threat of rot with ease. They are also more resistant to fungal infestation and rot, making them easier to maintain over the years.

Some of the durability class 1 timbers we recommend for retaining walls include Greenheart and Ekki.

Durability Class 2 Timbers

If you would prefer a wider range of more accessible timbers from which to choose, you can still choose a durability class 2 timber for your retaining wall. Oak, for example, is a durability class 2 but is still highly resistant to decay and has a long lifespan even when untreated. Cedar, Cumaru, and Iroko are other durability class 2 timbers we would recommend for retaining walls.

Treated Timbers

When moving outside durability class 1 and 2 timbers, you will need to treat your species in order to make it suitable for outdoor, ground contact use. But there are perks to be had from using a treated, less durable wood. Pine, for example, is lighter and easier to work with than the more durable timbers, and when coated with a natural Silica compound to create OrganoWood, it becomes far more resistant to rot and infestation.

Budget-Friendly Timber Options

When weighing up the cost of different timber species, the more durable options tend to come with a higher price tag. However, it is important to remember that you will save money on maintenance and treatments over the years, and with a projected lifespan of 25+ years at least, the cost-per-year of your retaining wall will be significantly less than if it is made from a cheaper timber which rots quickly.

If you are looking to save money or have a tight budget, we recommend chatting with a member of our team. We can help you find a timber species which suits your price range but does not make you compromise on quality.

Find Sustainable Timber

At EcoChoice, we pride ourselves on delivering sustainably sourced timber to projects around the UK. Whether for a retaining wall in your garden or a large project on a public site, we can supply FSC-certified timber to suit your needs.

To learn more about the right species for your retaining wall or to start an order, get in touch with us today. When it comes to your timber, we are always happy to help.