Understanding Trench Drains

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When it comes to choosing the appropriate trench drain for your project, it can be overwhelming. In this blog post, we’ll explain everything you need to know about trench drainage systems.

What is a trench drain?

A trench drain system is an linear drainage system used to remove excess surface water from an area, by use of a channel & grate. Without a drain, water can pool- potentially leading to damage to building foundations, driveways, and other structures.

How do trench drains work?

Linear drains rely on gravity to remove water from where it pools. When thinking about installing a drainage system, run length, slope & sizing need to be discussed with your installer or designer.

Benefits of Trench Drain Systems

The most significant and most obvious benefit of a trench drain is how it quickly and easily channels water away from certain areas of the landscape. A properly integrated trench drain will receive water from other areas in the landscape. To achieve proper integration of a trench drain, a landscape’s natural slope should lead water to the trench drain’s location, or a drainage system that concludes with water channelled into the trench drain.

Either way, the trench drain helps eliminate standing water by providing a means to remove it from the area, preventing water damage to houses, increasing safety & more.

In other cases, a drain can also increase safety. For areas like pool decks, footpaths & patios removing water quickly reducing slipping hazards. Having trench drains alongside public roads reduces the risk of hydroplaning
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trench drain installed on stairs for safety

Trench Drain Terminology

As you explore different options, you may find certain terms used interchangeably. This includes names like ‘trench drain’, ‘channel drain’, ‘line drain’, ‘grated drainage channel’. Each of those terms describes a trench drainage system- a system that removes water via a trough- or channel- with removable grates.

Difference Between a Trench Drain & French Drain

Trench drains are often confused with another type of common drains, French drains. While similar, there are a few major differences that should be considered when choosing between these drain types.

A French drain is a subsurface drain, unlike the surface-level trench drain. It helps drain excess water in the oversaturated ground, making them useful in yards that rarely flood, but face excess water during occasional rain events. They can help prevent serious and structural damage to the house.

The effectiveness of a French drain depends on the slope of the ground and the drain position. Their purpose is not to quickly move large amounts of water off of the landscape. Therefore, a French drain might work in a landscape with a low slope that receives a small amount of water, but a trench drain might be better for a landscape with a steeper slope that receives more water.

Installation is also a factor. French drains consist of a liner and perforated pipe installed in a trench. The pipe is then covered with gravel, making them more difficult to install than a trench drain.
French Drain
Source: The Spruce

Channel Materials

Trench drainage channels come in a variety of materials. Two main types include the concrete/polymer trench drain and polypropylene, which is what SABdrain channels are made out of.

There are many benefits to choosing a polypropylene trench drain. When compared to a polymer/concrete channel, SABdrain channels are lighter, easier to install, have a quicker flow rate and more strength than your standard polymer concrete channel.
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Grating Options

No matter what channel you chose, your new linear trench drain will require a grate covering. Grate options include but are not limited to cast iron, galvanised steel, stainless steel and even stone. View our range of products here.

The grate you choose depends on water volume, safety requirements and the location where it will be installed.

Firstly, the weight of anything running over the grate needs to be taken into consideration. Please refer to our blog post here on load classifications of grates.

Location of the grate such as proximity to chlorine water/salt water/ coastal areas affects which grates can be utilised as well.

Other elements such as water volume & sizing needs to be discussed with your plumber/installer as this differs between situations.

Trench Drain Accessories

There are a few accessories you may come across when researching your options for drainage. Most accessories aid with installation or pipe attachment whilst others are for locking down the grate to the channel.
This includes:
  • End Caps/End Stops
  • End Cap Outlets
  • Sprigot Offtakes
  • Debris Baskets
  • Install Clips
Please refer to our accessories page to learn more about relevant accessories for SABdrain.

Money Invested in a Trench Drainage System is not money down the drain

A trench drainage system is an investment, however it can save money & trouble in the long run. Investingin a drainage system can protect areas from serious and expensive water damage. Choosing the correct and most cost effective trench drainage system for your needs maximises the return on your investment.

Contact us today if you require further help with selecting a drain or to request a quote.