Beginner's guide to ducting pipe - Cotterill Civils

Beginner's guide to ducting pipe

When running a cable underground, whether that’s to carry power, motorway communications, lighting or utilities, you will need to ensure that it is protected from any damage and that it is easily identifiable to others. To do this you will need to ensure that the cable is run inside a duct. Here’s some useful information on how to ensure you are selecting the right materials for your application and to install the ducting safely.

1) Select the right material

Our ducting cable comes in both flexible and rigid structures. This includes Twinwall HDPE, solid wall Polyethylene and solid wall uPVC system. The type of ducting you select will depend upon your specific application. For example, if it is being used for longer runs, then flexible ducting will be your best choice. Whilst on shorter runs, rigid duct will be more effective. Twinwall duct is used where additional strength is required, such as below paths and roads.

If you’re not entirely sure which ducting you need for your application, don’t hesitate to get in touch with our team of experts. We can identify which of our products will meet your specification best, ensuring that you get the most out them.

2) Select the right colour

It’s important to select the right colour duct for your application so that you and others can easily identify its purpose when accessing it. Here’s a quick guide to the colours available and their typical applications:

  • Electricity – Black
  • CCTV – Green
  • Water – Blue
  • Gas – Yellow
  • Motorway Communication – Purple
  • Street Lighting – Orange
  • Street Lighting (Scotland) – Purple
  • Traffic Signals – Orange
  • Telecommunications (BT) – Grey

3) Make sure it meets industry standards

Depending on its application, ducting may also need to adhere to specific certifications. It is essential that you check this when purchasing your ducting from your supplier. Our ducting is manufactured to a high quality and meets the strict regulations of specific industry sectors, such as BBA certification by the highways or ENATS 12/24 Issue 2007/8 for C2 Application. Speak to our team of experts to get advice on this.

4) Install the ducting safely

When it comes to installing your ducting there are best practices that you can follow. For example, it is recommended that you use as few bends as possible and that your duct pipe follows an obvious route, like along a path or patio. The recommended depth to install the pipe is at a depth of 300mm to 450mm. See guide below.

  • Cable TV and communications – 250-350mm
  • Electricity (LV) – 450mm
  • Electricity (HV) – 450mm-1200mm
  • Gas – 600mm-750mm
  • Motorway communications – 450mm
  • Street Lighting – 450mm-600mm
  • Telecoms – 350mm
  • Water – 750mm

It’s also important to make sure that there are no stones on the bed of the trench that could potentially damage the pipe. To avoid this, many installers lay the duct on a bed of sand. To make the presence of the pipe easier to identify to others, it is also advisable to back-fill using a little more sharp sand over the top of the duct or use marker tape. All ducts must be provided with a draw rope after installation, unless it’s agreed locally to substitute the draw rope with a cable.

5) Different ways to join the duct

Depending on the type of ducting you are using, there are different ways to join the duct. For example, in the case of twinwall duct, the pipe is plain ended so to join it you will need to use couplers. These can be purchased separately. With flexible ducting, this pipe comes with a joiner attached at one end. When purchasing your duct make sure you check with your supplier whether you will need couplers to join your pipe.

6) Access to ducting

In cases where access to the ducting cable is required, we recommend our duct access chambers. These are generally used for Electrical or Telecoms Cabling.

Our team of specialists can provide you with expert advice on ducting. Call us today on 0121 351 3230.


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