Gas Plumbing

A gas engineer is needed whenever the pipework itself changes. We handle:

• New gas pipe runs: A new supply to a boiler, cooker, hob or fire, sized for the appliance it serves.
• Extending and rerouting: For a new kitchen layout, a boiler in a new position, or building work the existing pipe is in the way of.
• Gas for extensions and kitchens: Running gas into a kitchen extension or other house extensions, or moving the cooker point during a kitchen renovation, planned before floors and walls are finished.
• Capping off and disconnecting: Disconnecting an old gas fire, cooker or boiler, sealing the pipe with a proper fitting, or removing redundant pipework altogether.
• Replacing old or damaged pipework: Corroded steel pipe, or pipes damaged during building work.

Sizing. A gas pipe has to deliver enough gas to every appliance running at full rate at once. The size depends on the total gas rate, the length of the run and the number of bends. An undersized pipe causes a pressure drop, which shows up as weak hob flames or a boiler that locks out. This is common when a combi boiler is connected to pipe sized for an older, smaller boiler, so we check the existing pipe whenever a new or larger appliance is added.

Routes. Gas pipes must be supported, and sleeved where they pass through walls. They must not run inside a wall cavity, and pipes buried in a solid floor or wall need protection against corrosion. The pipe is kept clear of electrical cables.

Materials. Copper is the usual choice inside the home. Steel is used for some larger or exposed runs, and yellow polyethylene pipe only underground outside.

Bonding. The gas pipe near the meter is connected to the electrical earthing. If that pipework is altered, the bonding must stay in place; any new bonding is installed and certified through one of the routes the building regulations allow, through our domestic electrical installation service.

The gas meter is not part of your own installation: it is provided through your energy supplier, and the pipe up to it belongs to the gas network. Moving the meter is arranged through your gas supplier, who sends their own meter operator.

We handle your side: the pipework from the meter outlet to your appliances. We reroute it to suit the new meter position, keep the bonding in place, then test and recommission the installation. If building work affects the meter, speak to your supplier early, as the meter move is booked separately.

A gas tightness test checks that the installation is not leaking. The engineer first checks that the emergency control valve next to the meter shuts off fully (a "let-by" test). They then connect a pressure gauge, bring the pipework to test pressure, turn off the supply and watch for any drop over a set period, following the industry standard for domestic installations. If the pressure falls, the leak is found, repaired and the test repeated.

It is carried out before and after any work on gas pipework, and is often part of a landlord gas safety certificate check. New pipe is also purged: the air is cleared so that only gas reaches the appliances, which are then relit and checked.

Yes. The Gas Safety (Installation and Use) Regulations 1998 require gas work to be done by someone competent, and anyone doing gas work as part of a business must be on the Gas Safe Register. That applies to moving, extending or capping a pipe, even by a short distance, so builders and kitchen fitters who are not on the register must leave the gas pipe alone. On our projects, gas pipework is carried out by Gas Safe registered engineers, as the law requires.

The back of an engineer's Gas Safe ID card lists the types of gas work they are qualified for.

1. 1

   No sparks or flames: do not use light switches, doorbells or plugs, and do not smoke.

2. 2

   Turn off the gas at the emergency control valve next to the meter, if you can reach it safely and it is not in a cellar or basement. The lever is off when it sits at right angles to the pipe.

3. 3

   Open doors and windows, get everyone out and call the National Gas Emergency number on 0800 111 999 from outside.

4. 4

   If anyone feels dizzy, sick or has a headache, get them into fresh air and seek medical advice, as these can also be signs of carbon monoxide; see our emergency boiler services.

The gas emergency service makes the supply safe, which may mean cutting off an appliance or a section of pipe. We then trace and repair the leak on your side of the meter, retest the installation and restore the supply.