When Should You Choose Twinwall Pipe Over Single Wall?

Twinwall pipe, as the name suggests, is a pipe comprised of two HDPE walls with one inside the other welded together. The outer wall is ribbed and the inner wall is a smooth finish to help promote water flow. Sometimes, the pipes are perforated to allow water to seep in through the soil, despite being laid underground, and this is incredibly useful in heavy rain. These drainage pipes then help carry water to a designated collection point.

Where to Install Twinwall

Twinwall drainage is suitable for many applications due to the range for sizes available and the option of both perforated and unperforated pipe. However, it is more common for twinwall pipes to be used in heavily trafficked areas, as the outer wall gives the pipe superior strength in comparison to single wall pipe. It also comes in larger diameters meaning it can hold and transport more water.

Motorways and roads will often use twinwall as the heavy traffic moving above means extra support is needed. Twinwall is also often used under driveways to withstand the heavy load rating of cars and vans.

How to Install Twinwall

Twinwall is installed using a trench method where a trench is dug, in which the twinwall pipe is laid  before sidefilling/backfilling. For more information on how to install twinwall drainage, check out this guide we’ve already written!

How is Twinwall Different to Single Wall

It’s crucial to remember that strength is not the only difference between twinwall and single wall drainage. Although this is a key factor, it does not make the two interchangeable.

Twinwall is a rigid pipe that gets heavier the bigger diameter used, which is what allows it to withstand heavy loads and impacts.

Single wall (often land drains or similar) are flexible coils. They are easier than twinwall to transport and can be fit into trickier areas. They are used often in garden, agricultural and small-scale drainage projects.

Benefits of Twinwall

The main benefits of twinwall drainage relate to its strength and the variety of sizes being available – this makes it incredibly versatile for projects. It’s also great for flood management and attenuation. Although it is not common to choose twinwall drainage for smaller projects, there is nothing to say you couldn’t use a smaller diameter pipe for this and larger diameter for heavy load projects. Despite not always being the best choice, this does make pipe a suitable choice for any and every project.

For more information about twinwall, get in touch with our team, or shop here.