---
title: "Which pipe is used for gas?"
description: "Steel, copper of the right grade, or yellow MDPE underground — and in most jurisdictions only a registered installer may do the work. The ranked options, the techniq"
url: https://atoneplace.net/which/pipe-gas/
site: "At One Place"
---

# Which pipe is used for gas?

**Which pipe is used for gas?: Steel, copper of the right grade, or yellow MDPE underground — and in most jurisdictions only a registered installer may do the work.**

This entry exists to give the correct answer, which is that gas work is legally restricted almost everywhere. In the UK, anyone carrying out work on gas fittings must be on the Gas Safe Register; in the US and elsewhere, licensing sits with the state or municipality. The reason is that the failure modes are explosion and carbon monoxide poisoning, neither of which announces itself in advance, and a joint that passes a soap test today can weep later. Materials, jointing compounds, pipe sizing for the appliance load, ventilation and flueing are all specified in codes that assume a trained installer. If you can smell gas, do not look for the leak: turn off the supply at the meter, ventilate, avoid switches and flames, and call the emergency number.

## The options, ranked

*Ranked best-first for the stated job. The third column is why the others exist.*

| Option | Good at | Bad at |
| --- | --- | --- |
| Black steel (malleable iron fittings) | The traditional and still standard material for gas above ground in many markets. | Threaded joints require the correct jointing compound and skill. |
| Copper of the appropriate grade | Common for domestic gas runs where permitted, with brazed or compression joints as the rules allow. | The permitted grades and joint types are specified precisely and vary by jurisdiction. |
| Yellow MDPE | The standard for buried gas service pipe, colour-coded so it is identifiable when dug up. | Underground only, and it must be electrofusion or mechanically jointed by a competent person. |
| Corrugated stainless steel tubing (CSST) | Flexible and quick to install where it is approved. | Requires specific bonding to manage lightning-induced current, which has been the subject of safety alerts. |

## Technique that changes the outcome

1. Use a registered or licensed installer — in most places this is a legal requirement, not advice
2. Keep the appliance and installation certificates
3. Fit and maintain a carbon monoxide alarm in any room with a fuel-burning appliance
4. Have appliances serviced annually

## What goes wrong

- Any DIY alteration to gas pipework or appliances
- PTFE tape intended for water on gas threads; gas jointing compounds are specific
- Searching for a leak with a flame, or operating electrical switches where gas is smelt

> Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.

## Other pipe questions

| For | Use |
| --- | --- |
| Hot and cold water | Copper or PEX for most installations — PEX is faster and more freeze-tolerant, copper is more robust and takes heat without question. |
| Waste and drainage | Solvent-weld or push-fit PVC-u or polypropylene, at the right diameter and fall — and ABS and PVC cements are not interchangeable. |
| Central heating | Copper, or a barrier-grade plastic pipe — non-barrier plastic lets oxygen into the system and corrodes it from the inside. |
| Boiler condensate | Plastic, never copper, at a generous diameter with continuous fall — and insulate any external run, because frozen condensate is the classic winter breakdown. |
| An underground water supply | Blue MDPE for potable water, in one continuous length at the required depth, with no joints under a building. |
| Compressed air | Copper, steel, stainless or a purpose-rated aluminium or HDPE air system — never PVC, which fails explosively. |
| Irrigation | Low-density polyethylene tubing with barbed fittings for drip lines, and PVC or MDPE for buried mains. |

## Common questions

### Which pipe is used for gas?

Steel, copper of the right grade, or yellow MDPE underground — and in most jurisdictions only a registered installer may do the work.

### What should I avoid?

Any DIY alteration to gas pipework or appliances PTFE tape intended for water on gas threads; gas jointing compounds are specific Searching for a leak with a flame, or operating electrical switches where gas is smelt

## Related pages

- [Which pipe should I use for hot and cold water?](https://atoneplace.net/which/pipe-hot-cold-water/)
- [Which pipe should I use for waste and drainage?](https://atoneplace.net/which/pipe-waste/)
- [Which pipe should I use for central heating?](https://atoneplace.net/which/pipe-central-heating/)
- [Which pipe should I use for a boiler condensate drain?](https://atoneplace.net/which/pipe-condensate/)
- [Which pipe should I use for a buried water supply?](https://atoneplace.net/which/pipe-underground-water/)
- [Which pipe should I use for compressed air?](https://atoneplace.net/which/pipe-compressed-air/)
- [Which pipe should I use for irrigation?](https://atoneplace.net/which/pipe-irrigation/)

## Sources

- Typical range compiled from manufacturer specifications — At One Place (/about/)