Retaining walls done right will allow you to get the most value out of your land. They are great options for levelling off sloping areas to create a more usable level space for the kids to play on, or even just a nice garden bed. When it comes time to sell or rent your property the potential new owner or tenant will be looking at your landscape to see what can be used, or what will just become an unusable space or a troublesome area to maintain.
The engineering that goes into a retaining wall is best only left to an experienced contractor and something you want to guarantee gets done right the first time. Going with a cheaper quote may end up being an expensive nightmare if the retaining wall fails and needs to be redone. Often removing an old failing retaining wall can be near the cost of the new replacement, do you have the confidence your contractor has the experience and knowledge to be able to build a lasting retaining wall?
We specialise in 3 different types of retaining walls and can help you plan and construct a retaining wall from anything for a basic garden bed to an engineered retaining wall with a house or driveway going directly beside it. Below we will quickly go over a few points on each to help work out which may be best for your application.
Lifespan: Good, 10+ years.
A treated pine retaining wall is the starting point for consideration. However when using 50mm pine sleepers we recommend not going higher than 2-3 sleepers (or 400/600mm high) in some cases as pine sleepers can sometimes tend to bow outwards with too much pressure behind the wall even when backfilled correctly. However generally speaking any retaining wall only 1-3 sleepers high 50mm sleepers will more than suffice. Once you get to 600mm or higher you need to consider using either 75mm pine sleepers or 50mm hardwood, however every retaining wall is different and we will recommend the best option for your budget and goals.
Lifespan: Better, 15+ years.
A fair sleeper choice for any height retaining wall. Hardwood sleeper prices are higher than pine prices however you get what you pay for in terms of life expentency and strength or load the wall can handle. 50mm hardwood sleepers are fine for most cases where the only load will be soil behind the wall, however in cases where more load is required such as a slab for a shed or house being built close to the wall you may need 75mm sleepers, we will discuss your requirements with you when onsite quoting for your job.
Budget: High end
Lifespan: Best, 50+ years.
If you require a long term or just the best solution, a concrete retaining wall is it. Concrete sleepers come in a variety of different styles and colours from textured to flat and use galvanised steel posts for uprights. Another benefit of using this system is it is great in tight spaces or where a wall is required to be as close to the cut as possible as the sleepers run in the same line as the posts. The cost for a concrete retaining system is higher than a timber retaining wall due to added material costs and labour, however you will have that peace of mind knowing your new wall is not going to need replacing for decades to come.
Make sure to compare all your quotes to check you are getting quoted for the same product. Heres a few questions you may want to think about asking your contractor to verify before going ahead with any quote.
What size posts and sleepers (or sometimes known as whalers) are being used? Sometimes contractors will quote using only 50mm sleepers as posts when 75mm is required for any retaining wall post section. Or will often only quote for a 50mm sleeper behind the wall when really a 75mm sleeper may be required.
We only use 75mm uprights for all retaining walls. 50mm or 75mm sleepers will depend on a few factors such as what material will be used for the wall, and how much force the wall will be holding once backfilled.
Do they offer a guarantee their wall will do the job it requires?
We've been offering retaining walls for a long time, and so we will only offer a product that we know from years of experience can hold upto the job.
Does the wall include an adequate drainage system and geo fabric?
Unless requested, all our retaining wall systems over 400mm high include agi pipe, drainage gravel and geofabric standard and backfilling standard. Our quotes are also fixed price for machine hire, you wont get a random hourly bill at the end of the job. Retaining where only 1 or 2 sleepers are required will often not require drainage.
Does the price include backfilling, and are the machine hire costs fixed or charged hourly on the job?
Our builds include backfilling and fixed machine hire costs all accounted for in your quote. The price doesnt change after the job has begun.