Gas connection methods

When connecting to the Vector gas network, the gas main in the street will be dug up and exposed (usually a hole no more than a metre square) and a ‘T’ connection will be fitted.

The gas service will then be laid to the property in one of three ways, depending on the property’s soil conditions. Ideally, the underground connection to the property will be made using trenchless techniques such as thrusting or drilling. If soil conditions don’t allow trenchless laying, a narrow open trench, known as open cut, will be dug to the gas meter.

Directional drill

This is the most effective way to install a longer gas service. A mechanical ‘mole’ is used to tunnel below ground to where the meter will be placed.

Directional drilling means there only needs to be two small holes dug; one at the beginning and one at the end of the pipeline, thus disruption is minimal. Generally this method applies to longer services, over 30 metres and up to 100 metres.

Thrust

This is generally used when a service is less than 30 metres as the maximum length this machine can thrust at a time is 15 metres. Two pilot holes are dug and a bore is thrust through from the lead hole through to the end hole.

Open cut

This is the most common method used when the surrounding ground has high rock content and drilling or thrusting cannot be used. A narrow trench is dug from the gas main in the street to the gas meter to lay the gas service.

Note - these methods described above cannot be used in areas where the soil has a high rock content.

Providing your own trench

Developers of new buildings, subdivisions, or other construction projects may prefer to supply their own trench. This is known as pipe in trench (PIT) or sometimes dig your own trench (DYOT). Developers can provide their own trench for a gas service alone or for multiple utility services, such as electricity, water and telecoms.

The developer or customer is responsible for all trenching and reinstatement from the site boundary to the meter position. The Vector service provider is responsible for trenching and reinstatement from the gas main to the site boundary and for laying the gas service pipe throughout.

Where a trench is opened for the laying of a gas service only or for multiple utility services, it must meet the following requirements:

the trench should run the whole pipe length to enable the pipe to be laid in one continuous piece
for a service to a single property only the trench must be at least 500mm deep from finished ground level
for a service to multiple properties/sites, the trench must be at least 700mm deep from finished ground level
Siemens Energy Services will supply yellow warning tape, which must be placed at a depth of 150-300mm below finished ground level
the trench should be large enough to ensure there is 150mm clearance radius between the gas pipe and other utility services
the trench should be backfilled with fine material such as sand to ensure the gas pipe is not damaged.

Providing a services trench - trench requirements

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Please note:

a completed wall is needed to fit a gas meter; this must be fitted prior to livening the service
if using a recessed meter box, this must be identified to your gasfitter at time of requesting your PIT
if the gas pipe has not been connected to the gas meter please do not undertake any concrete work or landscaping over the gas service.

We recommend that regular contact is maintained with the gasfitter, keeping them informed of the building status and date requirements for the gas service.