What’s The Difference Between A Soakaway And A French Drain?

Did you know that as many as 90% of incidents of structural damage to basements is a result of improper drainage? This could all be avoided by ensuring correct drainage when building or developing a property but there are several options to choose from. 

Two of the most popular types of drainage are the soakaway and the French drain. Both are very effective but they may each be suited to different applications. 

In this guide, we’ll cover the basics of what you need to know when it comes to soakaway vs French drain and tell you when to use each one. 

What Is A Soakaway?

Soakaways are primarily used for rainwater and these come in the form of plastic crates. They’re lightweight and are ideal for use in both commercial and residential properties.

The way that a soakaway, sometimes called a soakaway crate, is used is by placing it into the ground. Depending on the size of the drainage system you are looking to create, you can install as many soakaways as you need. What’s more, you can customise the shape of your drainage system as the crates are designed to fit together.

When using soakaway crates, it is important that you wrap them in some kind of non-woven geotextile. Following this, you’ll need to cover them with shingle and then add your soil. Leaving out the layer of shingle runs the risk of soil getting into the drainage system and affecting its capacity. 

The Pros And Cons Of A Soakaway

Soakaway systems are quite easy to install and don’t cost the earth so they’re great if you’re looking for a convenient solution to rainwater drainage. Moreover, with this type of system in place, you’re taking a lot of pressure off of the main drainage system so there’s less risk of it becoming overwhelmed.

In addition to this, there are some water companies that offer a rebate to customers who use a surface drainage system such as soakaway crates. So, if you’re looking to save money in the long run, this is an idea worth considering.

Of course, as with anything, there are downsides to the soakaway and this includes the potential for increased maintenance. Generally speaking, soakaway crates don’t require too much maintenance but when things go wrong, they can be a pain to fix. For example, there’s the risk of soil or debris getting into the system and blocking it. Plus if you have poorly draining soil, this type of system just won’t work. 

On top of this, you have to consider that the soakaway system must be placed a good distance from the property otherwise there is a risk of foundation damage, especially if the system isn’t functioning correctly. 

What Is A French Drain?

French drains are designed to drain flood water and groundwater; just like soakaways, they’re suitable in both commercial and domestic situations. What’s great about them is that not only are they very effective, they’re also discreet. But we’ll look more closely at the pros and cons shortly. 

With a French drain, the system is placed into the ground at a depth of between 0.2 metres up to 6  metres. How deep you lay the system will depend on the size of the project. For example, a large commercial project would require a much deeper system.

Installing French drain systems is also an easy job but the key is to use high quality materials. Again, you’ll need a non-woven geotextile as well as shingle. You will also need to make sure that the drainpipe you choose is made from perforated plastic.

The Pros And Cons Of A French Drain

One of the main advantages of having a French drain system is that it will do a very good job of keeping water away from the property and will protect the foundation from water damage. On top of this, these systems largely ensure that there aren’t any puddles or other standing water which could affect your lawn or any plants growing in your garden.

French drains are also a viable long term solution since they are one of the most long lasting types. But as with the soakaway, there are some issues to consider when making a decision. 

For example, you may need to dig up areas of your garden that have previously been landscaped meaning that there will be cosmetic work required after the installation. While this is not only inconvenient, it can get very expensive. Of course, you have to factor in that this will be a long term solution so you may see the additional costs as an investment. 

Also keep in mind that installing French drains in colder climates will cost more as the system will need to be buried more deeply. In addition to this, any maintenance can also be more expensive.

The Importance Of Good Drainage

Any part of a building that has direct contact with soil, like the foundation of your house or the cellar, also has regular contact with water. These might include seepage, groundwater and many other types. 

When this water dams up, there is a serious potential for damage to the building. When you have good building drainage as well as an impervious blanket in the cellar wall, this ensures that the building is protected from humidity. The result is that water can be drained away safely and without causing any damage.

There should never be an instance where a building is not built with sufficient drainage, the structural issues that may ensure simply are not worth it. As we mentioned at the beginning of this article, it’s thought that as much as 90% of all basement structural damage could be prevented if the correct drainage was used. 

One of the main benefits of this is that you can then use a cellar space as additional living space. Many people choose to create a games room, bedroom or chill out space in these parts of buildings and they can do so without the risk of mould and damp when proper drainage is in place. 

When To Use A Soakaway And When To Use A French Drain

It’s evident that there is a clear difference between a soakaway and a French drain. The two are used for different reasons so it’s really important to consider what you’re trying to achieve from your project. 

Both systems can be very effective when they are correctly installed but you’d want to opt for a soakaway if you are only looking to tackle surface water. These systems send any standing water back into the soil.

On the other hand, a French drain is used to direct groundwater away from your property by sending it underground. These systems are ideal for protecting against structural problems.


It’s clear to see that the soakaway and the French drain are both incredibly efficient types of drainage system. However, they are used in different situations so it’s important to choose carefully so that you end up with the right level of protection for your property. 

There are pros and cons to each of these systems which you’ll also need to take into consideration. While the French drain may be more costly and come with a higher maintenance cost, there’s less chance of a need for this type of work and these are long lasting systems. 

Driveway Expert